Entry V ERS does not exist in T687 (check entry)

Hi,

I am very new to SAP, just started learning. While creating a custom pricing procedure, I tried to copy the standard pricing procedure RVAA01 and when I try to save it, it gives me an error like 'Entry V ERS does not exist in T687 (check entry)' .

So, what should I need to do to fix it and create my custom pricing procedure?

I would appreciate yor help.

Thanks,

Sam