My Budget Car Rental Deposit Not Refunded After Return

I rented a car from Budget at Ostrava Airport on 03.08.2024, and they took a deposit of 20,000 CZK (€800). When I returned the car, they assured me the deposit would be refunded within a few days. It’s now 17.08.2024, and I still haven’t received the refund. Budget is claiming that the bank is holding the funds, but my bank confirms they haven't seen any refund transaction. This delay is unacceptable, and I want my deposit back immediately. I trusted Budget for the rental, and now I’m frustrated with the lack of communication and the unresolved issue. Please address this matter urgently!