Hi all, sorted and now running a dream! Found it was a combination of things... Old fuel (drained it out and filled it back up with new fuel), took out all the spark plugs, cleaned them and when I checked the crank shaft sensor the cable connector fell apart in my hands 😩. Replaced and it fired up as if nothing was wrong!
Thanks for all your help!
(sorry for the delay posting this reply - covid has put a damper on things!)