Please pay back my refund as promised

I paid this company in cash to do my screed flooring. They failed and didn't do leveling accordingly after many days of false promises to come.

We agreed on full refund as they were at fault. They are now claiming they are doing a breakdown calculation. What breakdown as they are the ones who didn't deliver on their part.

They promised to fully refund me and I have proof of such and now they are saying they are calculating, calculating what?