@niterhk There are a few things you can try but before you do anything please do the following first if you have not yet done so.
1) Take a screenshot or note down of your player ID. This can be found either by clicking the wrench key in the game or in Apple's Setting > PVZ2 (player info). Just in case you need to contact EA for help.
2) Register your email with EA (in the game and get 100 free gems). This ties the account to your email and it also allows the same account to be restored onto other devices, this includes crossing over to another platform, on Android as well as IOS.
Once the above 2 key items are done, you can try re-install the game as a fresh install either on the same device or another device and see if the issue is fixed. Do make sure to enter your age as an adult (18+) so you can register your email again with the same email address to get an option to reload your saved account via email confirmation.
Please note, if you are using two iPhones, do not use the Apple's clone service by pairing the two devices together via bluetooth as this will just transfer the corrupted data over, you will need to do a fresh installation so the new user data could be reconstructed.
EDIT. Forget to add that if you do a fresh install, you will be treated as a new player for 2 days, during this time, the shop items will be different, you will get a minimum set of offer restricted to new players, the old comprehensive offers will return after two days.