API /sapi/v1/convert/getQuote Error -2008 "Invalid Api-Key ID."


I am new here. I am testing the API /sapi/v1/convert/getQuote.

It works perfectly for the USDT → SOL transaction, but the reverse, SOL → USDT, does not work and returns the following error:
{“code”:-2008,“msg”:“Invalid Api-Key ID.”}

  • Example request: https://api.binance.com/sapi/v1/convert/getQuote? fromAsset=SOL&toAsset=USDT&fromAmount=0.00591304& timestamp=1716906509381&recvWindow=5000& signature=1b9fdff4cbe6db9890ec0c197d29b058af276e22aefda14a4c63ee4400c623ff

  • Language: C# (HttpClient);

The error message does not reflect reality, as USDT → SOL works and the code is the same.

Has anyone experienced this or could offer some advice? I have checked the keys and everything is fine.

Thank you.