Wooden floor sanding specialists

I got the contractor in to sand and seal my floors. I have small parquet flooring blocks. He did the whole house in 2 days as well as 'sealed' the floors with a very 'expensive' sealant. All looked good when they finished. About 2 months ago I noticed rough patches and when walking , some blocks sound loose. I told him that it probably needs another coat of sealant. I am still awaiting his comeback. Told me he was busy in Gauteng and was quite rude. This job cost me R20 000. This was 2 months ago. He hasn't even bothered to contact me.