Incorrect account getting picked despite of SLA

There is a custom SLA in place however, only for a couple of transactions incorrect account is getting picked and it is resulting in invalid status journal. 

The SLA is set in a way that if the Task capitalizable flag is N, the account should be picked based on Expenditure type to Account mapping, If the flag is set to Y, it should pick the account from the class code assigned to the project. The project in question here is an operating project and the expenditure type used in the transaction has an account mapping in the mapping set. Yet, the accounting combination is created with the class code value as account. The SLA has worked on numerous other such transactions, but only two transactions are failing