Hello...
My ISP uses a mikrotik server to control the network
i asked him to allow me downloading 15 gb with full speed and after i consume the 15 gb the server limit me to download with 1mb speed (120 kb per second) and this ocurrs every month (renewable)

he told me that he needs a rule that he does not know ...so if any can help me and tell me that rule .... I would be very grateful !!

Maybe he can add BURST limit in the queue tree or even set the FUP daily through radius and resets every 12 hours or so