Trial Plan - no transparency on used up credits

I am using Travis CI to learn (from Udemy courses) and get a new job.
I signed up for a trial account and received 10000 credits. My builds were very few on 2 repos and after about a month and very few builds, it seems I ran out of them. It’s not clear how they were used up!
My ability to use Travis is disabled and It seems I am forced to the $69/month if I wanted to continue.

I am

told I will lose all my credits if I switched (no idea if I have any left!). This seems hardly fair. May I know how the credits were used, how much I have left and what other options I have besides switching to the $69/month?

As a side note, in today’s market with so many looking for new roles and learning, I wish Travis would offer more generous plans.

Thank you