Kicked from Server : Steam authentication failed

Today I installed the game excited to play it after the new patch, I played a a few games and logged off, then I logged on again but everytime I tried to join a game I would get this message: Kicked from Server : Steam authentication failed.

I tried multiple things like logging off and logging back in on steam, Cheching my antivirus and preventing it do to do any action on my game folder, Doing the EAC repair, Restarting my pc but nothing worked.

I would like to get some help because I searched and saw that this problem was already fixed with a hotfix but I still have this problem. I really want to play the game since I already payed and this is preventing me to get my moneys worth.
I would apreciate any help from any devs or fellow players.

Hello @asuM,

We're sorry that you're having this issue. Can you please try the following steps and see if the issue still persists?

  1. Press the Windows and R keys from the keyboard to open the Run dialog box and type: steam://flushconfig
  2. Click OK.
  3. Clear the Steam - Download Cache.
  4. Run Insurgency: Sandstorm once logged to your Steam account.