If you've been prompted to pay more, don't worry, this is expected behaviour, not an error. Your plan includes a monthly credit allowance, and once it runs out, some actions draw from a separate credit balance called Main Credit.
How it works
ByThen has two credit types:
Free Credit: your monthly allowance for standard features like script generation and Key Visuals. Resets every billing cycle and can't be topped up.
Main Credit (MC): used for production from Storyboard onwards, and as a fallback when Free Credit runs out. This is what you top up.
Once your Free Credit is fully used, eligible actions draw from Main Credit instead.
If Main Credit hits zero, generation is blocked until you top up.