The first step to fix mouse (or keyboard) issues is to disconnect and reconnect the mouse on the computer, or to connect the mouse to another USB port.  Also, if you 're using a Wireless mouse replace its batteries. 

It's NOT the mouse! It's a plarium thing!! I am having the same issue!!! It's ONLY not working in RAID and only when clicking certain things...mainly for me, the X button in the top right corner to back out of a screen...and and won't work to open "rewards" tab on top left side of screen. This has been happening alot lately..and it's super annoying right now, since it's during a fusion and during CvC..and i can't really play the freakin game!!!

I have been having the same issue randomly over the past several weeks.  For me, the X button in the top right corner of the screen is unresponsive.  I can click other items on the screen, just not the X.

have same issue with X button now

yea same here, it randomly happened today. can't close stuff anymore. the X button is unresponsive 

Same here, X button not working. 

Edit: I also cannot read the News, after pressing "Read More" nothing happens.

after the update have same issue with X button now

Hell, it would be nice if they even acknowledged they are aware of the issue. Time for a new game to play before the world implodes.

i have the samething happening, Hit the X button and nothing happens, this is only happening on pc as 

playing on mobile works fine, I mostly play on pc so unitl this is fixed I will not be logging in for awhile.

The x button is not working for me also. Plus I can usually hit esc and get off of that screen but not working either

Yes, same here for me with the X thing.

Funilly enough, pressing ESC on the screen also doesn't change anything. I suppose some sort of update will come up soon.

Really sucks because it's during a fusion, ando for me it was working fine yesterday and I didn't change anything on my PC or network.

Been online grinding all morning and suddenly the X button stops working for me also.. 

To be honest, it seems most of the game is unresponsive now. Just tried to change champs on CB and couldn't. It looks like it might be a DDoS attack on their servers, as this has happened before.

Gues we better check discord for more info.

Edit: They're aware and working on it

i

Edit #2: Toggling auto-update on and off several times in Plarium play worked for me. Turns out I didn't see the forge pass thingy before and when the game launched again I did, and now is responsive as normal.

I'd suggest you trying that out!

I had the same problem with the X not working.

I solved the problem by Reseting the Cache in Settings / System Preferences of Plarium Play