Confused about the new Late Payment Fees module

I’m very confused about the new Late Payment Fees.

Our case of the use of the Late Payment Fees is to charge one-time to any defaulted payment. I have commented previously in this forum a proposal to add an addition of one-time charge of an amount or a percentage upon the creation of the invoice.

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However, the new release of the Late Payment Fees, which I anticipate an improvement towards it and perhaps solved my case for the one-time late payment charge.

Here are the questions that I find it confusing - it looks like it didn’t solve my case.

  1. Why the check boxes are not able to uncheck. The system forces the creation of those late payment payments and incurred monthly.
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  2. If I do not want to add the late payment fees to a particular invoice, is there is a way to delete it so that it will not appear the following month?

Did you read the section of this Guide, Determine late payment fees manually: https://www.manager.io/guides/10584?