Hi Dharmkrit,
In one of your earlier posts, you have mentioned that you have assigned G/L accounts by selecting table 1. This is probably where you might be going wrong.
Please follow the below steps to cross check your entries and you should hopefully have a solution.
(1) First of all, start from the account determination procedure and check which procedure is assigned to the billing type.
(2) Check the account determination type that is maintained in the procedure.
(3) Check which access sequence assigned in that condition type
(4) Check which table/tables have been maintained in the access sequence
* In most probability, you would have maintained a different table in the access sequence while you are trying to assign your G/L accounts to some other table
* Also, since you say that this error is only for a particular account determination type, check if you have maintained the correct combination of application/chart of account/Customer account assignment group/material account assignment group/G/L account in the correct table. However, this combination of fields depends on the table that you have used in the condition technique.
I suggest that you write your entries down while checking the flow. This will give you a clear picture if a connection is missing somewhere in the condition technique.
The customer/material account assignment groups are just keys (two digit codes) and their determination has nothing to do with Z1/Z2/A1 or any other code that you have defined in the system. The main determination is purely based on the condition technique and how correctly you have maintained the connections between the tables, access sequences, types and procedures. Just recheck these entries and you should be able to resolve the issue.
Hope this helps 
Regards,
Sumita Mittra