Exactly the duplicate of https://bitcoin.stackexchange.com/questions/73444/copay-does-not-work-in-iphone5-ios10
Don't worry, it has been reported: https://github.com/bitpay/copay/issues/8382
It's not only you, other people seem to have the same problem.
Just wait until they release a fix for it.
EDIT: It has been fixed. Please update the app!