If you wonder why rate dropped drastically, it's because minex project can't compete with competitors anymore.
The only real USP of minex was the promised credit card. But they lost the race against their competitors:
https://m-scmp-com.cdn.ampproject.org/c/s/m.scmp.com/business/article/2162873/hong-kong-blockchain-start-rolls-out-asias-first-cryptocurrency-visa-debit?amp=1
I don't want to spread FUD, but in my personal opinion this project is dead and the value will be 0 soon.
Maybe that's why support doesn't react anymore. Guess they prepare to close down and draw some money out of the project.
I know it hurts to sell with huge losses, but it's still better to get something back than nothing.