Breaking my watch!

I bought my watch from this store and received great service, but when I went in to replace my battery after having the watch for two months, they said they can do it and went to the back of the shop came back after a while in the back of the shop. The person who helped me returned the watch and didn’t point out that he had damaged the watch, we realized this on our way home. The watches battery compartment is broken and we cannot open it. We got hold of the manager she was very helpful and told us she will replace the watch but we can’t get hold of her and we have not been called back as promised to come collect the watch.