How do I prevent iPhone 14 Pro from switching to default keyboard?

Hi, I am currently using Microsoft Keyboard. i like which functions are, swipe etc. Now since few days iphone keeps switch to default keyboard. with passwords ok, i got it but it keeps doing anywhere. I am writing it now with switched keyboard. It is hsrder for me causing so many writing typos, have to switch to 123 instead having dot or emojis wherever i want. Someone also having trouble? How to make my iphone 14 pro working normaly?

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