If you have no credit balance showing on the account overview page, you’ll then need to add a payment method and fund the account with purchase of more credits.
The usage page doesn’t otherwise show a credit account balance, only your non-use.
Credits are granted when an OpenAI account is created, which can be when you first discovered ChatGPT and not necessarily when you have then considered API, which was once the only purpose of an API account. Free credits then expire three months after.
You could send a “please give me more free credits” message by the help assistant at help.openai.com, but it may be more expedient to just fund your account - plus you then unlock GPT-4 models and higher rate limits also.
On the lower right of the help page, there should be an assistant icon.
“Help” is also a menu icon within the account management of platform.openai.com.
The icon should launch a little dialog that allows you to send a message to OpenAI staff. You can try the Edge web browser if you just don’t see the icon at all.
Sending a message to beg for more free money is just a possibility, they may not be able to grant more credits simply because you let the first round expire without any use.
Simply paying $5 for real money credits is a guarantee to get you quickly going at full steam, though.