Hi Serghei,
If you still have a bank account with the same provider, you'll have to contact the bank as normal refunds usually takes up to 15 business days. Provide the ARN in refund status page as it will help the bank track the refund.
You may also check this article for reference:
https://www.airbnb.com/help/article/1967
In case that the bank confirmed that no refund yet, obtain documentations from the bank maybe email or written document that refund is not with them. Then contact Airbnb support so they can escalate to the right team.
I hope this helps.
All the best,
Upfish Management