Invalid Request

Today, I had an important interview and was using the AI service for preparation. However, I repeatedly received an "Invalid Request"

error while trying to use the AI. Despite the requests failing, 0.5 credits were deducted twice, resulting in a total deduction of 1.0 credit.

Since the requests were unsuccessful due to this error and I was unable to use the service, I kindly request that the deducted credits be restored to my account. I would also appreciate it if you could investigate the reason behind the "Invalid Request" error to help prevent this issue in the future.