Accounting lines are swapping when clicked on Next icon in grid

Hi, I am on 9.2 FSCM, 8.55 PT with Update 25. In an invoice custom page, contract accounting lines are getting displayed. There is a custom view which populates data on this grid. Each contract  line will have multiple accounting lines. It is set with occurs count - 3 for this grid.  

Issue Scenario:

Consider there are 3 contract lines for a contract.

Contract Line 1 - has total Accounting Lines 5  (has Activity id - 001 for all 5 rows)

Contract Line 2 - has total Accounting Lines 4  (has Activity id - 002 for all 4 rows)

Contract Line 3 - has total Accounting Lines 3  (has Activity id - 003 for all 3 rows)