The most probable reason for that error is, the system is determining Faulty GL account. You need to change the GL account which is not a reconciliation account.
You probably would need help of an FI consultant. Anyways below are the steps you would need to do,
Goto FS00 - Enter the G/L account and company code,
In the Account group if you have reconciliation account then , you cannot use that account here. Use different account.
Goto OBYC , Click on transaction to get GBB, Enter the chart of accounts assigned to your company code. (If not known goto OBY6 and check the same.) goto Account modifier BSA change the account there.
If you have entered the G/L account manually, enter a different account or cancel the account entered, so that the system determines an account automatically.
Then try using Tcode MB1C.
This should work.