Cannot Unapply Receipt in Fusion Receivables Cloud Service

When do unapply receipt for the transaction that has adjustment, this error come out:

1. A document sequence does not exist for the current document, even though the ledger option Enforce Sequencing for Receivables is enabled. (AR-855682)

2. ORA-20001: (AR-855636)

3. An Unexpected error occurred while reversing the adjustment . Contact your help desk (AR-856802)

After submit Service Request like below:

PROPOSED SOLUTION 

================== 

SELECT * 

/* SR3-15016089661 */ 

FROM FND_DOC_SEQUENCE_CATEGORIES 

WHERE NAME = 'Adjustment Reversal' 

Result: 

CODE NAME TABLE_NAME DESCRIPTION 

Adjustment Reversal Adjustment Reversal AR_ADJUSTMENTS_ALL Adjustment Reversal 

However, the above category is not assigned to any document sequence: 

SELECT 

/* SR3-15016089661 */ 

* 

FROM fusion.FND_DOC_SEQUENCE_ASSIGNMENTS 

WHERE CATEGORY_CODE = 'Adjustment Reversal' 

Result: No Data Available 

Hence, you need to go to task Manage Document Sequences and assigned the Document Sequence Category 'Adjustment Reversal' to the appropriate Document sequence (I assume AR_PJA_SEQ_ADJUSTMENT) and its Legal Entity 

This assignment it is required. 

CAUSE DETERMINATION 

================== 

document sequence category 'Adjustment Reversal' is missing the assignment to a document sequence