Mautic not allowing to add new custom fields

Your software
My Mautic version is: 2.16.3
My PHP version is: 7.2.34
My Database type and version is: MYSql 5.6

Your problem
My problem is:
I was creating some new custom fields in mautic and got this error “You have reached the limit of custom field allowed in your database”. So I deleted some custom fields but it didn’t work. It is not allowing to add new custom fields and showing the same error.

These errors are showing in the log: You have reached the limit of custom field allowed in your database

Steps I have tried to fix the problem: Tried after deleting some custom fields.