Cause 

This issue appears due to wrong account group selection in M.R. ledger.

Solution

In order to resolve this issue user needs to change the M.R. account group with "Sundry creditors (field staff)" by following the below steps:

1. Go to Books > All ledgers(Alt+L).

2. A Ledger accounts window will appear in which user will select the M.R. ledger.

3. Press F3 function key on selected ledger.

4. Select Ledger details.

5. A modify ledger window will appear. Click on Modify.

6. Now, In 'Account group', the user will select "No".

7. An under group window will appear in which the user will select the Sundry Creditors (Field staff)  and then press enter.

8. Then press Ctrl+W to save changes.