Bad service and really not happy

On Mother's Day,my husband decided to spoil me to some lunch..Got to ClearWater Mall and went to a resturant called The Pop Up Grill.We ordered lamb shank with mash and the food was cold..We asked the waiter to ask the kitchen staff to warm up the food for us,he came back with the lb shank but the mash was not there..He tells us that the kitchen staff says the mash is finished.How can the mash be finished in a resturant were u serve lamb shank??Anyway we were not impressed and told the waiter we want our mash coz we harldy ate it so we shocked how is it finished..After 15 minutes of waiting we decided to leave and not eat there anymore.We offered to pay for the drinks of which we were told not to pay for and that we will get called for a comprimentry meal for the inconvenience..Well 2 weeks down the line and still no call.I have never ever in my life receive such bad service in a resturant