bad service received from accounts/credit department

I submitted my child phone for repairs as the phone did not switch two weeks ago, a week later we received a call stating that they could not fix it as it has physical damage, upon arriving at the store to check why now they say they could not fix it, we found the phone badly damaged spoke the lady by the name of Sonto and Emma they both had bad attitude and said they is nothing they can do and we can talk to the the whole day as nothing will change.

the other guy who also work there was able to confirm that the phone did not have physical damage when we brought it however the manager there said she has nothing to do with it, she said it was not his business. we have never been disrespected like this as customers. my child also tried to explain the the store manager that the phone did not have any physical damage the only reason we brought it was it could not switch on.