Your laptop was out of guarantee when you had it repaired.
Dell repaired it - the process took 30 days.
During that time you had a "few apologies" - presumably for the time it was taking.
I assume that the machine is now working well?
You wrote to Dell to complain......, but what about? I have to confess that 42 phone calls in 30 days is an awful lot - what were you phoning about?
What is it that you expect from Dell now?
If you can provide a little more detail it might help us to get a perspective on what went wrong. It's not unheard of for a laptop repair to take that long by the way.