If your perks have appeared to reset to 0 completely, it is likely that your game client is having trouble reaching the Steam backend where your stats are saved. Perks Fail to Progress, reset to Zero ( 0 ) or revert to an earlier state Item or inventory is Missing - Purchased and Earned If it still doesn't show, verify your firewall and be sure to enable traffic for KF2 (as you seem to only play solo now), some bugs in firewall can prevent traffic even if it is allowed, so destroy the rule in firewall, restart computer, recreate rule. Some players may experience issues with receiving drops in game if they have security software such as an antivirus or firewall blocking the game. Players Not Receiving Item or Event Drops PC Game Locks Up At Server Browser / No Servers Displayed / Failed to Join Server / Connection To Host Lost SteamDB can be used to find all available servers. Click on 'Start', then select 'Run', or if run is not present type it into the search box, type 'cmd' and press Enter or click 'Ok'.
New dedicated servers are added regularly, as such this is not a complete list. Taken from the Steam FAQ at Killing Floor / Monday Night Combat / Homefront BT Home Hub and Thomson router telnet fix tutorial - YouTube and amended slightly.
The most common cause of this is corrupt files in the user directory or missing prerequisite files. This is a list of dedicated servers available on Steam and SteamCMD. exe has stopped working or hang on launch
