wow. dude, I have never seen such strange bug. 

Screenie of negative timer, get in firefox, chrome and edge.

Usually opening world map and coming back in or opening

boosts menu and closing sorts it, sometimes it is stubborn and lasts

a good 5-6 minutes.

This issue is still going on.

Now once timer goes negative attempting to boost fixes it by getting an error

saying there are no tasks to boost.

This works even if you have no boosts by clicking buy and apply.

I find opening the offers and hitting refresh there, will reset/correct the task timer

happens allot on browser vs mobile

still happening, waiting 6 mins after a 5 min task. boosts, world map and back not working for me :)

I get this issue frequently too - one workaround I use is to keep some "help" jobs for my clan available. As soon as it jumps to negative time I help one clan member and it fixes the timer.

Evidently it would be far better if they fixed it properly but faster fix than refreshing game etc.

Hope it helps you.

quick fix, when the timer is at 0 or negative boost it,,, it always works for me..today there was no problem,, by the way. ie if you boost a 0 or negative timer, the response always becomes,,, you cant boost a cleared task, and then the timer stops and I can claim the task  and you still got your boost left!

This Bugg been happening for weeks now,,, and i still cant log in with my 32-bit system must use my 64-bit one.

 the computers have the same performances just different Systems... 

Swedish Viking force, 

What I found when this happens, and it works everytime:

I have to same thing as well, not all the time but periodically.

to over come I pay or use boost to complete the task even though its in a negative state.

System then informs me that I cannot do this as the task is complete.

Once back on task screen I can claim the task / reward and on to the next.

Works every time for me....no need to exit or reboot.