bad news for me - I think to have to leave bithopper

as I come today to my PC I see that no Internet connection is for a few hours...

I believe that the network traffik is to big for me (I have 20 GB/month) and in 8 days this volume is over (I have done not much another in net - therfore it must have been the traffik of bithopper...)
Is there any way to make it less traffic?
(I'm now with another acount here because volume for this month is over...)
TIA