Default campaign entry is deleted from carryover adjsutment table when there is no adjustment to do

Steps:
--------
1. Deploy an order with 4 BA/BL with budget type as follows,

C1 - MIN
C2 - MAX
C3 - FIXED
C4 - DEFAULT

2. on day t+1, run ABU for the above account and verify carryover table for the campaigns.
3. customize the campaign budgets on the same day as follows and redeploy,

C1 - MAX,
C2 - FIXED
C3 - MIN
C4 - DEFAULT

4. on day t+2, run ABU and verify carryover and carryover adjustment table.
5. Carryover adjustment table have entries as follows,

Example:
campaign ID Date Carryover Adjustment
C1 2019-01-03 6.45162
C2 2019-01-03 6.45162
C4 2019-01-04 -12.9032

6. do not do any customizations on day t+2 and run ABU on day t+3.
7. Verify carryover adjustment table.

Problem: After running ABU without making any customizations on day t+2, campaign C4 is getting deleted from the carryover adjustment table. Adjusted carryover is not getting added to the Default campaign.