How to delete customer account

I want to delete customer account that pay his money

Processed customer accounts can not be deleted. If a customer deletion is made on the data, payment accounts, stocks and reports will be affected.
Must not be deleted

But i want to clear all detail when customer pay bill

Perhaps if you explain your reasoning an alternative solution might be possible.
However deleting as described will not be possible.
PS. this is not an issue, issues are for bugs etc - I have changed to a question.