Welcome to the community!
In which portion of the Metro were you trying to use cellular services? As far as I am aware, certain portions of the Greenline have not yet been completed for service (see here).
Were you unable to use any your services or just data? Since the mobile network in the metro is a joint effort, it's likely your phone would need to roam on that network (possibly as Fido-EXT or extended coverage). If that's the case, you would need to enable roaming data to use data services. Did your phone receive any signal at all?
Hope this helps 😀