Can we restrict the dulicate credit-memo request creation

Hello Friends,

I have a process in which we create an invoice 'X' and after that we create credit memo request with reference to main invoice 'X', and follow to this credit memo is created with reference to credit memo request.

Now the problem is multiple credit memo requests has been created with reference to same invoice and then job will create multiple credit memo's for same invoice with reference to credit memo request.

So i want some suggestions, how i can restrict the multiple credit memo request creation for same reference.

Thanks in advance.

Yash