1048 Column 'first_validity' cannot be null

Hello Support,

Using CB Subs with various plans published on the frontend.

Scenario:
Unregistered user selects a plan, completes registration and clicks sign up.

Page refreshes and displays the following error:

1048 Column 'first_validity' cannot be null

Force the browser to refresh and the following message appears:

You are already signed up with this username and password.
Your registration data has now been saved, but your subscription isn't active yet. You need now to pay the subscription:

The basket summary is displayed and the user can continue with the payment transaction.

How can I prevent the error message please?

Specifications:
Joomla 4.0.3
Community Builder: 2.6.3
CB Subs: 4.5.2+build.2021.10.07.10.13.17.f313a5004

Thank you,

Problem solved, just went through all the plans and reconfigured them which has cured the issue.

Is the plan selected a free plan? or has a free initial price? What's the duration for the plan? Try editing and re-saving your plan within CBSubs > Plans then retrying as we have made some fixes that may not be applied to plans created before the fixes.