diff --git a/src/aiovodafone/api.py b/src/aiovodafone/api.py
index c7a1f01..e4baeb6 100644
--- a/src/aiovodafone/api.py
+++ b/src/aiovodafone/api.py
@@ -99,6 +99,10 @@ async def _get_page_result(self, page: str) -> aiohttp.ClientResponse:
             allow_redirects=False,
         )
 
+    @abstractmethod
+    async def convert_uptime(self, uptime: str) -> datetime:
+        pass
+
     async def close(self) -> None:
         """Router close session."""
         await self.session.close()