Predator z321qu monitor won’t turn on - blue power led flashing

I went to turn on my monitor the other day and it wouldn’t come on. I did a power reset and now all it does is flash on and off. The blue led flashes on and off as well as a green and red led underneath. The osm won’t come on. I brought a new power supply and do cable neither of which made a difference. My pc works fine as I’ve tried it on another monitor. I tried a hdmi cable and that didn’t work either. The pc recognised that the monitor is plugged in as it comes up as a secondary monitor on control panel.

I rang acer support and they offer no advise parser from me having to send off the monitor for repairs which isn’t open until the 11th so should call back then 😐.

any advise would be most welcome!