For anyone reading this, this a suggestion based on my personal experience.
If you haven’t already check out Patrick Mckeown and his research and findings into nose breathing and it’s relation to asthma. He has a really interesting and helpful book called ‘Close your mouth’ - which outlines breathing techniques in order to manage and significantly reduce asthma symptoms.
Personally this has massively helped me cope with my symptoms and realise that I was a mouth breather and this was not doing me any favours. He has loads of content on YouTube and his website is: buteykoclinic.com.
A great place to start is ‘Ben Coombers Radio’ podcast on Spotify episode 599 called ‘Less oxygen is better’ (it’s near the top) he interviews Patrick Mckeown and he goes over everything high level so easy to understand.
Hope this can help someone like it helped me.
Ta-ra!
***adding Lysistrata's advice to this***
'Very glad to hear it's helped! For anyone else reading though, perhaps be careful with the taping at night. It can be fine for some people but some physios I have met, while all for learning nasal breathing, are less keen on the mouth taping for people with established respiratory problems. It probably isn't ideal especially if you also have ongoing sinus/nasal issues blocking your nose.
Anyone considering this should probably check with someone knowledgeable who knows your medical situation about the taping and whether it's suitable for you. '