Dio Bug testing

import time

file = open("Logins.txt","r")
logins = []
for line in file:
    user = line.strip("\n")
    user = user.split(",")
    logins.append(user)
file.close()

auth = False
end = False

while end == False:
    option = input("1.Log In\n2.#\n")
    while option != "1" and option != "2":
        option = input("Invalid entry, please try again\n")
    
    if option == "1":
        valid = False
        found = False
        count = 0
        while True:
            count += 1
            username = input("Username:")
            if username == "#":
                print("\nReturning to previous page\n")
                time.sleep(1)
                break
            for i in logins:
                if i[0] == username:
                    found = True
                    if i[1] != "-":
                        valid = True
                        break
            if count == 3 and valid == False:
                print("\nYou appear to be having trouble with your username, please contact me.")
                end = True
                break
            if found == True and valid == False:
                print("You appear to be entering an authentication code. If so, please enter # to go back, and select # instead.")
                print("If not, your username is incorrect. Please try again, ensuring it is spelt correctly and capital letters are in the right places.\n")
            elif found == False:
                print("Your username is not recognised. \nPlease try again, ensuring it is spelt correctly and capital letters are in the right places.\n")
            else:
                break
        
        if valid == True:
            count = 3
            while True:
                count -= 1
                password = input("Password:")
                if password == "#":
                    print("\nReturning to previous page\n")
                    time.sleep(1)
                    break
                if i[1] == password:
                    auth = True
                    size = int(i[2])
                    end = True
                    print("\nWelcome",username,":)")
                    break
                if count == 0 and auth == False:
                    print("\nToo many failed attempts, you have been locked out.")
                    end = True
                    break
                else:
                    print("Incorrect password, " + str(count) + " attempts remaining.")

    if option == "2":
        valid = False
        count = 0
        while True:
            count += 1
            code = input("Authentication code:")
            if code == "#":
                print("\nReturning to previous page\n")
                time.sleep(1)
                break
            for i in logins:
                if i[0] == code and i[1] == "-":
                    valid = True
                    print("Authentication code verrified.\n")
                    break
            if count == 3 and valid == False:
                print("\nYou appear to be having trouble with your authentication code, please contact me.")
                end = True
                break
            if valid == False:
                print("Your authentication code is not valid, please double check its digits and try again.\n")
            else:
                break
        
        if valid == True:
            check = "N"
            while check == "N":
                username = input("Please choose a username:")
                if username == "#":
                    print("\nReturning to previous page\n")
                    time.sleep(1)
                    break
                for i in logins:
                    while i[0] == username:
                        username = input("Username is already taken, please choose something else:")
                check = input("Please confirm you wish to set your username to " + username + "(Y/N)?").upper()
                while check != "Y" and check != "N":
                    check = input("Invalid input.\nPlease confirm you wish to set your username to " + username + "(Y/N)?").upper()
            
            print("\nHello " + username + "\n")
            check = "N"
            while check == "N":
                password = input("Please set your password:")
                if password == "#":
                    print("\nReturning to previous page\n")
                    time.sleep(1)
                    break
                print("Please know this password may be accessible to me or others if I cannot work out how to hide them.")
                check = input("Do you still wish to set your password to " + password + "(Y/N)?").upper()
                while check != "Y" and check != "N":
                    check = input("Invalid input.\nDo you still wish to set your password to " + password + "(Y/N)?").upper()
            
            print("\nYou are almost set up now, just one last thing.\n")
            print("For the best user experience I need to know the width of your screen.")
            check = "N"
            while check == "N":
                print("Please select from the 5 options below which fits your screen best WITHOUT spilling over.\n"\
                        "(you may wish to change your font size to get the best fit possible)")
                print("\n1." + "#"*148 + "\n\n2." + "#"*198 + "\n\n3." + "#"*248 + "\n\n4." + "#"*298 + "\n\n5" + "#"*348)
                while True:
                    try:
                        size = int(input())
                        if size > 0 and size < 6:
                            size = size*50 + 100
                            break
                        print("Invalid input, please try again")
                    except:
                        print("Invalid input, please try again")
                check = input("#"*size + "\nPlease confirm this fits your screen best WITHOUT spilling over (Y/N)?").upper()
                while check != "Y" and check != "N":
                    check = input("Invalid input.\nPlease confirm this fits your screen best WITHOUT spilling over (Y/N)?").upper()
                
                print("\nThank you, now you are all set up.\nAny of the choices you have just made can be changed in settings at any point.\n\nPlease enjoy :)")
                end = True
                auth = True
                
        for i in logins:
            if i[0] == code:
                i[0] = username
                i[1] = password
                i[2] = size
                break
        
        file = open("Logins.txt","w")
        for i in logins:
            add = i[0] + "," + i[1] + "," + str(i[2]) + "\n"
            file.write(add)
        file.close()