SAP Error “Complete allocation structure P1” during wbs settlement using t-code CJ88

Here I share my experience in my client about error during settlement WBS using t-code CJ88. This error appear when finance staff trying to settle their WBS (budget).The root cause is there transaction with in cost element use on goods issue transaction but the cost element is not member of allocation structure.

The message from SAP look like below :

Complete allocation structure P1
Message no. KD 503

Diagnosis
During settlement, the system puts the sender debits into groups (assignments), which are settled using the same settlement cost element. The settlement assignment is made in the allocation structure, which is stored in the settlement rule for the sender (under settlement parameters).
Cost element 5272310 cannot be assigned to a settlement cost assignment in allocation structure P1, and therefore it cannot be assigned to a settlement cost element.

Procedure
Possible solutions are as follows:

If the posting under cost element 5272310 was made to the sender because of an incorrect entry, and you can reverse the posting, and do not need to update the allocation structure. You only need to reverse the incorrectly assigned posting before repeating the settlement. Exception: For an investment measure with a line item settlement, you need to extend the allocation structure, even after the reversal.
If the posting was made correctly, you can do the following:
a) You can assign a different allocation structure to the sender: In the master data maintenance for the sender, choose “Settlement rule -> Goto -> Settlement parameters” and then enter a different allocation structure.
If necessary, also check whether the correct allocation structure is entered in the settlement profile. The allocation structure is defaulted in the settlement profile when you create sender master data or when you maintain the settlement rule.
You can update allocation structure P1

And here the solution :
Solution :
Alternatif #1. Attaching G/L account into allocation structure
Procedure : 1. Reverse all transaction causing error related to WBS and G/L account.
2. Attach G/L or cost element into allocation structure.
Path IMG :
Project System > Costs >Automatic and Periodic Allocations >Settlement > Settlement Profile > Create Allocation Structure (T-Code: no specific T-Code only ‘general’ SPRO)
3. Settle WBS Element using T-Code CJ88
Note: Not Recommended

Alternatif #2. Reverse the transaction causing error in one period on each transaction.
Procedure : 1. Reverse the transaction using t-code MBST.
2. If not possible using journal correction t-code FB50.
3. Settle WBS Element using T-Code CJ88.

Note : to see status GL Account posting manual / automatic use t-code FS00