How can I refund my payment to a hotel apartment for bad service?

Greetings!

I rented a serviced hotel apartment in Abu Dhabi on a long-term lease (6 months) paying 6 months lease amount (AED 23000) in advance.

After occupying the apartment on 11/04/2022, I found lots of insects and bedbugs in the room. Notified the management. However, every time I was told it is fixed.

Later one night, the bedbug bite was intolerable and I was forced to vacate the serviced apartment in the middle of the night (on 28/04/2022).

While vacating, I was told by email that the advance amount deducting the period of stay will be refunded within 7 working days.

Now as of today (30/06/2022), I am not refunded. No one answers my calls and physical visits, I am told they are not available. The amount agreed for refund after deduction is AED 20,070.

Please suggest what I should do to get the refund for the failure to provide the service. I have the receipt of payment and email from the management regarding the refund.

Pictures of the bedbug bites are also available.

Thank you.

B.