Connection lost 3 times in a row! on wave 16+.... WTF!

That's pretty much it.

Edit: do i need to port forward trendynet or something? if so whats the ports?

I was on the wave 24 on survival mix mode, it was a pleasure to encounter a connection lost at this time seriously. I almost uninstalled the game and ask for a refund.
Fix the issue with steam or no body will not even play this game anymore.

We should be able to save where we are considering we have an infinite building phase. I lost almost 10 hours of my life and all my partners. I wont be playing this game until you guys patch this or answer me a solution.