Claiming the security deposit from the landlord held illegally

My landlord is stating he will hold AED 1700 from my deposit for maintenance: AED 1500 for a new bathtub and AED 200 for cleaning the bathroom after repairs.

I handed over the apartment (repainted and cleaned) to the agent that I rented it from, and when I asked him for my deposit during the handover, he said I have to deal directly with the owner and gave me his number.

On 4th July I sent a message to the owner asking for my money and he replied he is out of the country and when he comes back he has to go and check the apartment first.

On July 18th he sent me a message informing me of the charges. When I asked for receipts (I was sure there are none as the apartment was in perfect condition), 4 days later he sent me a screenshot of "quotation", dated 20 June.

When I asked for the actual payment receipts he sent me exactly same screenshot (a day later) with "receipt" instead of quotation (no payment method mentioned, or VAT, or any other mark how was the payment done).

What can I do in this case?