If you reach the order limit of a lower plan, you can upgrade to a higher plan by paying the proportional difference to the higher plan and continue using Zenamu without any limitations.
In the "Subscription Management" section, click on "Upgrade subscription to a higher plan."
The plan will be upgraded immediately.
You don't have to worry about paying for both the old and new plans at the same time; you'll only pay the proportional difference for the remaining period.