Hi! Welcome to the forum!
Nope! It’s currently independent of whether you have a chat plus account or not. You can go to https://platform.openai.com/usage to see if you have any credit.
What model did you use?
In any case, that’s a langchain issue - langchain (depending on your setup) injects a ton of stuff into your context. It’s also possible that it’s a misconfiguration. In LangChain.
LangChain reddit can probably help you better: Reddit - Dive into anything