How to run MacBook Testflight app in iPhone instead of iPad?

What should i do if i wanted to use iPhone device on MacOS? Previously when i have only iPhone in destination, it appeared as "Mac (Designed for iPhone)", but after i added iPad, it auto changed to "Mac (Designed for iPad)". Now it's running on iPad device in TestFlight when opening from M1 Macs. How do I get it to run on iPhone device?

How to run MacBook Testflight app in iPhone instead of iPad?
 
 
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