very bad service

End April 2015 we ordered 4 block out roller blinds from the above company. Delivery date was suppose to be 10 working days. After 21 working days they came to install the blinds. 3 of the 4 blinds were measured to big to fit into the window sill. They altered the blinds in such a way that 2 of the blinds are so skew it is a disgrace and look like secondhand blinds. They tried to rectify the blinds without success. The manufacturer suggest that they replace the 1 blind which is damage beyond repair. In July we still did not received the new blind. I asked them to pay back my 80% deposit and collect the blinds. They refused to pay back my deposit and up to date we haven't heard of them!!! So, up to date we are still having our 'new secondhand' blinds without any response from their side. Shame on Mr & Mrs Knobel for the disgusting service they provide.