If the accrual period is closed, you cannot submit accruals for that period.
The deadline has passed.
The period cannot be reopened.
Brightflag Support cannot reopen it.
Your client cannot reopen it.
What Should You Do?
You must contact your client directly and ask them to:
Submit the accrual in Brightflag on your behalf.
Once the accrual period is closed, submission through your vendor account is no longer possible.