Unfortunately like many areas of medicine (at least in Canada), sleep specialists will do a sleep study, and unless your sleep is sues fall cleanly inside a condition they can treat (cpap for apnea for example) you are on your own except for some one sized fits all advice about sleep hygiene.

If you don’t have restful sleep and don’t have apnea, and you have already tried the basics like melatonin, not using electronics before bed etc, you have few choice but to accept it or try to find your own answers.