[wflann]

How long ago was this? In the past couple of years, I believe the backend systems have been integrated so you can use Tokyo-specific cards in Osaka and vice versa

[munmaek]

This March. I wasn't able to use Suica for the Osaka busses.

[9nGQluzmnq3M]

Were you using some minor bus company? To a first approximation, all Japanese IC cards are compatible these days.

https://en.wikipedia.org/wiki/Suica#Interoperation