I was experiencing the same issue after I deposited well over the $1 GPT-4 API access threshold. I received access automatically after ~24 hours but it was frustrating at first after not finding any information in the GPT-4 access thread detailing the possible delay period. I did submit a support request via OpenAI’s platform using the “help?” tab which also may have resolved the issue on it’s own but I recommend waiting first as to not overload support. As for the API documentation there is plenty of documentation on GitHub as well as this forum that maybe you can make use of, also ensure you’ve read the API reference. I have yet to have had any issue with finding thorough documentation regarding the API.
Have you tried documentation? OpenAI Platform
Switching the language of provided examples to python may help sometimes…