If they took a different way from where you were they’re on detour. I stood at a corner for about 30 minutes until I realized this. The only way to know is through the SEPTA app, the app sucks it’s difficult to find your exact stop then you have to understand the streets and everything to tell exactly where the detour is but it sounds like it was a detour.

Sometimes they put signs up at the stops sometimes they don’t.

For everyone else commenting, one other guy said it but yes if the bus is “full” they won’t stop unless someone else is getting off. I’ve never been passed up but I only get on/off at market st which is always a stop.