third_party_settings.commerce_license.interval.interval doesn't exist

In ProductVariationTypeFormAlter.php it looks to me like $variation_type->setThirdPartySetting('commerce_license', 'interval', $interval); expects an integer but is instead getting an array?

I encountered the same error and added a fix that worked for me.

I can confirm that patch #3 works. Thanks @vitaliyb98

Had the same error, and patch #3 worked for me, too. Thank you @vitaliyb98 .

I've submitted a merge request to speed up the review and commit process.

This should probably use unsetThirdPartySetting().

Also, what circumstances would have the NULL?