Quoting bod:

Bugün çok mektuplar yazmam lazım.
Resmi mektuplar yazmalıyım hoşlanmıyorum

Quoting bod:

I was trying to say:
"I don't like having to write formal letters"

Quoting hexagon00:

I don't like having to write formal letters
Resmi mektuplar yazmaktan hoşlanmıyorum

Quoting bod:

Quoting bod:

But it is the "having to" that I don't like......not the "writing formal letters".
Do we not distinguish between these two in Turkish?

Quoting caliptrix:

hexa is right. However, I think, if you really want to say (express) that what you don't like was "have to it", you can use it.

... yazmak zorunda olmaktan hoşlanmıyorum.

By the way, as it is because of using -mak more than once, you can use "sevmiyorum" instead of "hoşlanmıyorum":

... yazmak zorunda olmayı sevmiyorum.

That is good one, I guess.