Blesta Thank You Message After Payment

[Asif]

Hi! I have developed a custom payment gateway(non merchant, cointopay) for blesta 4.2. Everything is working fine but there is a problem that is 

when the callback function is run after paymnet, it check the status and update to database according to status(paid,pending, declined and son) but it always shows me one message that is "Your transaction is being processed". I want Thank You message according to tranasaction status as

if Paid {  Your transaction has been approved }

if Pending { Your transaction is in pending } 

if Declined { Your transaction has been declined }

 

Is there any way to override Thankyou message??