What is wrong with my dishwasher?

I have a 2 year old Beko Dishwasher (original cost £250)

When running a cycle the machine takes nearly twice as long as it should do. (i.e.90 minute cycle takes 150 minutes)

It takes ages to switch from Rinse to Dry mode-this is where the additional time is taken. When the cycle eventually finishes the dishes are not hot and are basically damp.

I have been advised £60+vat for a callout plus spares for someone to take a look.

What is wrong and is it worth repairing?

I would be grateful for any advice