ORA-04091: table ... is mutating, trigger/function may not see it

I'm trying to fire this trigger but I get ORA-04091: table ... is mutating, trigger/function may not see it
since I'm querying the same table the trigger is firing on.
I tried declaring pragma autonomous_transaction; but that wouldn't update the status on OF. it did however fix the mutation error.
The OL table can contain many records with a status of 1 or 2.
This trigger should fire whenever these statuses are changed and check if all are =2. If so then udpate the status of OF.
How else can I count(*) OL without querying it so as to avoid mutation error & not use a pragma declaration?



CREATE OR REPLACE TRIGGER OL_SPLIT
AFTER UPDATE OF TOORDERID,STATUS ON OL FOR EACH ROW

DECLARE
v_count            number(20);

BEGIN  
  IF (:old.status = 1 and :new.status = 2)  then
        
            select count(*)
            into v_count
            from OL b
            where b.orderid = :new.orderid and b.status = 1;
            
            IF v_count = 0 THEN                   
                  UPDATE OF
                  SET FORMSTATUS = 4
                  WHERE ORDERID  = :new.orderid;
                  commit;                        
            END IF;            
 END IF;            
END;
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