I have a scenario for first time house buyer.

Siti is first time house buyer.
Ali is not first time house buyer.

Siti wanted to buy a house of less than 500K
Siti name will appear in SPA, without Ali
Siti and Ali joined name to apply bank loan

Bank say MOT should get 50% discount
Solicitor say MOT should get 40% because loan is under 2 names

Which side is correct? 40% or 50% discount?