…is beyond me (informal)
W1A- s1ep2:
Ian has to travel from London to Manchester to take part in a five-minute radio interview. He argues he could have done it over the phone. (Why I have to go is beyond me= I can't understand why I have to go).
https://youglish.com/getbyid/75589689/is%20beyond%20me/english
https://youglish.com/getbyid/67277838/is%20beyond%20me/english
https://youglish.com/getbyid/12160849/is%20beyond%20me/english
https://youglish.com/getbyid/102655666/is%20beyond%20me/english
https://youglish.com/getbyid/50191382/is%20beyond%20me/english