Ticket Issues:

I have created PO with Freight (FRB1) amount and then I did GR. 

After that, I realised the freight amount is wrong in PO.  I am going to change the freight amount in PO, but the field is grey even though the GR have been cancelled. 

How can I change the freight amount in PO?

Solution:

Do not worry about the freight amount if you have put wrong amount in PO and you have finished GR also. 

Cancelling the GR will not help you as the Field gets greyed once GR done. Please process the GR with the freight as it is. Then process the MIRO-Invoice option as per GR. 
 

Under Payment

1) Once done find out the Amount you need to further pay to the vendor. 

2) Run a Sub-sequent debit in MIRO-subsequent debit option against the same PO.
 

Over Paying

1) If you want to get back some money from vendor then 

2) Run a subsequent-credit in MIRO-subsequent credit option against the same PO.
 

Note:

But do remember that you need to run the subsequent txns only after MIRO-Invoice run.

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