Credits fully depleted/wiped out by a single API request twice in a row

I am experiencing an issue with my credit balance and would appreciate your help in resolving it.

After running out of credits, I purchased a new one-time credit pack (not a subscription). I then made a single request using Chat GPT SOL, and it instantly depleted my entire credit balance to zero.

Thinking it might have been a one-off glitch, I purchased credits once again. Exactly the same thing happened: I made just one request, and my balance was immediately wiped out to zero.

Could anyone please explain what the issue might be? This has never happened before.