despite the fact that I have purchased this for a year it just won't allow me to use it on my device. I had a monthly plan then cancelled and upgraded to annual a few months ago
We have looked into your Adobe account registered using the same email.
There was a subscription for Acrobat Premium, which is now canceled and inactive.
You can check the same from your Adobe account itself: https://account.adobe.com/
If you have purchased it again under a different email, you need to use that email to sign in.