BUDGET PHONE SUGGESTION which is better Galaxy a50 or a30? any other sugges

Hi
Im looking to buy a phone for my dad. I will need to buy the phone unlocked. he currently has the galaxy j7 but its always lagging and restarting in a loop and is unusable.
Is the new galaxy a line up reliable or should i be looking elsewhere?
he will mostly be using it for calling, whatsapp and facebook and no gaming. he wants something that has good reception and loud speakers!
im looking for a phone that i dont have to change in another 2 years.
i cant buy iphones
thanks