1. System problem: The bank's system may be out of order or the network connection is unstable, which makes it impossible to click the loan button. You can try refreshing the page or try again later.

2. Permission: You may not have enough permission to borrow money. In some cases, only certain customers or certain employees can borrow money. You can consult the bank staff for specific operation authority requirements.

3. Insufficient loan amount: If your loan amount has reached the upper limit or is insufficient to support your loan demand, you may not be able to click the loan button. You can contact the bank staff for details of the loan amount.