Shirts Lost by laundry service

About a month ago I put my shirts in to be laundered at Morrisons. I came back 6 days later to collect them, but they weren't ready. I was away for a week and when I finally went to collect them they gave me 5 shirts but 4 weren't mine. Currently I've had a couple of emails from Timpson who are contracted to handle laundry services by Morrisons. The upshot is they can't find my shirts and I have no idea what my timescales and rights are. Any thoughts out there please?