Carryover Rounding rule is not working in Carryover Fast Formula

Summary:

Dear Team,

We have a carryover rounding rule for our client as a result we have created a Fast formula. However, this is not working for us. Can anybody help us why it is not working.

/*Rounding Rule

20.1 -> 20.5

20.2 -> 20.5

20.3 -> 20.5

20.4 -> 20.5

20.5 -> 20.5

20.6 -> 21

20.7 -> 21

20.8 -> 21

20.9 -> 21

*/

L_carryover = IV_ACCRUAL

L_DEBUG = ESS_LOG_WRITE('L_carryover=' || to_char(L_carryover))
L_DEBUG = ESS_LOG_WRITE('IV_ACCRUAL=' || to_char(IV_ACCRUAL))
L_DEBUG = ESS_LOG_WRITE('L_Nov_Acc_Balance=' || to_char(L_Nov_Acc_Balance))

carryover = 0

IF (L_FF_DEBUG = 'Y') THEN(
L_DEBUG = ESS_LOG_WRITE('L_Accrual : ' || to_char(L_carryover) )