Can’t sleep for coughing - any tips please?

Steam is great , with a warm drink. You can of course put vics vapour rub in the steam water. I got a little steam inhaler from Boots .

Night Nurse liquid works for me

When my Dh had a dreadful cough that was keeping us awake at night the doctor prescribed nasal sprays. We were baffled by that but 'bingo' it did the the trick!

One was an anti-allergy spray, the other a simple saline spray.

Vicks (or other) vapour rub on my chest, so that I can breathe the fumes, does it for me. I've also heard that if you put it on the soles of your feet it can work in some mysterious way.

Covonia Night Time is excellent. It has to be asked for over the counter in a Pharmacy to get the full strength version. One swig and I don't cough all night.
I hope you will improve soon.

Could be a postnasal drip starting the cough reflex. My only suggestion is hot drinks and sitting well propped up with pillows. Hope you feel better soon. ?