Second, continue to handle the agency. The reason why the loan can't be processed is that your credit information is not good, or your bank's flow is not good. Find a solution to the problem, or consider getting a loan from another bank.
Third, find a guarantee company to buy a house in full, and it will be much easier for you to get a bank loan with the property as collateral after the transfer.
Although there is no agreement in the contract, generally speaking, it is the buyer's obligation to apply for a loan. So this situation is very beneficial to you, so try to find a solution from yourself. If it really doesn't work, it can only be solved through consultation with the owner.