I had the exact same experience as you
Over 6 months I though I had fixed the 'no start' issue only to have it come back again
No rhyme nor reason each time
I tried EVERY suggestion on the forum, and it would work for a while and then....... back again

I eventually followed the 'send off the SKREEM and ECU'
I am in NZ and it took a month to get there and back But
I installed the recoded unit and.................. it started straight away and I have not had the problem since