You can check battery health under Settings > Battery > Battery health.
If they actually replaced your battery with a new battery, you should see Maximum Capacity saying 100% and Cycle Count should be relatively low, considering however long ago it was that it was replaced. So if they just replaced it yesterday, the cycle count should be less than 3. Cycle count refers to how many times your phone has charged fully since the battery was installed. I’ve had my iPhone for almost 3 years now and on 920, for an example of what you shouldn’t see if the battery was actually replaced recently.
There’s a possibility that they replaced it with a battery that Apple doesn’t officially recognize. I doubt it since they’re an Apple authorized retailer/repair shop, but it’s a possibility.
People have noted weird things happening when parts of their iPhone get replaced with non-authentic Apple parts. Like if you use a generic touch screen instead of an actual Apple part, it can disable FaceID. Apple says it’s part of security, which may be partly true, but it’s mostly because Apple wants you only using their genuine parts and not buying a cheap alternative.
You can check battery health under Settings > Battery > Battery health.
If they actually replaced your battery with a new battery, you should see Maximum Capacity saying 100% and Cycle Count should be relatively low, considering however long ago it was that it was replaced. So if they just replaced it yesterday, the cycle count should be less than 3. Cycle count refers to how many times your phone has charged fully since the battery was installed. I’ve had my iPhone for almost 3 years now and on 920, for an example of what you shouldn’t see if the battery was actually replaced recently.
There’s a possibility that they replaced it with a battery that Apple doesn’t officially recognize. I doubt it since they’re an Apple authorized retailer/repair shop, but it’s a possibility.
People have noted weird things happening when parts of their iPhone get replaced with non-authentic Apple parts. Like if you use a generic touch screen instead of an actual Apple part, it can disable FaceID. Apple says it’s part of security, which may be partly true, but it’s mostly because Apple wants you only using their genuine parts and not buying a cheap alternative.