Check whether the sub still available when handling the request am: d883d46f81 am: c99ace8f04 am: 4654520a43

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/services/Telephony/+/15974128

Change-Id: I80ca077f610194202f8d8aea349097ba69775bd5