wireless charging and new iphone 12 pro max

This was an interesting experience. mine does not still charge and it has the most recent operating system update. i took the wireless charger into the apple store and it worked on the staff member's phone but not mine. diagnostics = nothing wrong with my phone. But why it worked on their new wireless charger. Their only solution was to send it for repairs - but wait nothing is wrong with my phone as they said to me - or for me to get an exchange in phones from my provider from whom I purchased it. When do Apple admit they have a problem so they do not make us feel we have the problem when we go into their stores?