Ok, so certain afternoon i was really tired, so i decided to go to sleep for a nap. I could only sleep for 1.5 h or so no point in attempting MILD. I try WILD instead. i loos feeling in my body, suddenly the ‘background’ before my closed eyes turns from black to purple! (later on i ruled out any possibility in change in light conditions). And then… my eyes randomly open! 
. whenever something interesting happens e.g developing phosphenes my eyes always decide to involuntarily open. What can i do about it?
If your eyes feel like they might be trying to open, you could try reverse blinking. Start with your eyes closed and then open and rapidly close them again. After a minute or so you should be ok since your eyelids will be tired enough to stay closed.
This happens to me too, though my eyes start cracking open rather than just fully opening all of a sudden. Generally I just fully shut them and I can continue more or less where I left off, as my body still has that numb and tingly feeling. I find it’s easier to keep them closed when I let them close naturally to begin with rather than forcing them shut.
I keep having this problem and I was waiting to see if someone else was having this issue. I’ve found over time that the reason this kept happening (my eyes randomly starting to creep open, especially during WILD attempts) was because I was too stressed. I’m a really tense person naturally so it’s hard to let go, but once I got the hang of making myself relax, my eyes stopped doing this. The method I use to relax is a body scan, which is also useful for relaxing myself during the day when I’m tensed up due to PTSD. Basically you just focus on your feet, and then your legs, and so on and if any of those areas are tense or otherwise uncomfortable you readjust them or consciously focus on un-tensing them. Repeating this process a few times has given really good results so far.
Sometimes my eyes would start to open and I’d be excited, thinking I was beginning hypnagogic imagery but it was just my eyes creeping open, and boy was that frustrating. But again, just convincing myself to relax has been enough to relieve this problem but of course what works for me may not work for you. Good luck!
Thanks for responses guys.
Tried the reverse blinking and it significantly decreases eye opening, tonight I’ll try body scan untensing 
I’m so glad I came across this topic! I’ve just discovered LD last week and was trying WILD last night and my eyes kept popping open no matter how hard I tried to keep the closed.