Describe the Amendment Process

Under B2b amendment table 9A ,amend that invoice to Zero value & under B2c table 7, add the same.

Done as you said, then Validation error is showing in B2B amendment. That is *Processed with error*.

How B2C invoice uploaded as B2B ?., as B2C do not have GSTN number( Consumer) and B2B transaction required GSTN number.
( B2C transaction means registered person selling the goods to Unregistered person)!

Hello Prasad Nilugal Everyone knows that recipient's GST Number is required while uploading B2B invoice. The problem here is that the above B2C invoice was uploaded as B2B invoice in GSTR1. That is an error.
My question is how to fix this error.It is preferable not to really understand the content of the question and answer accordingly

My point is how you entered B2C invoice in B2B when both required GSTN number.If you add B2C transaction in Table 4 of GSTR1, it will show error.

first of all b2c invoice cannot be uploaded as b2b ... but if it is so as then you need to talk to helpdesk.