Bad service

I'm utterly disgusted by there service. I took my phone to there canal walk branch to be fixed on the 17march as I had a free screen. I was told it would be ready in 7 to15 working days up to date I'm still having lots of problems with the store. Manager told me the customers all rather pay the to get screen fixed as it's a problem so my question is if you give a free screen why is your customers paying.