ISSUE: iPhone validation issue while entering English Characters using Japanese Keyboard

Application: HTML,Javascript,Angular web Application

Issue: In Iphone/Ipad while trying to enter English characters using Japanese keyboard in the input field the japanese keyboard freezes and stops working after entering the first character.

Root Cause: Two validations given in the onInput call back method causes the issue. when the validation are removed keyboard is working fine

1.for converting lowercase letters to uppercase

2.Some Character are not allowed so they are replaced after input