Sometimes it happens with any ISP(particularly the private ones) who disrupt services to remind the customer,that his/her recharging of account is nearly at its end and the time of recharging/renewing is drawing near(PRE-PAID cases).In case if you had any POST-PAID account,such problems do rarely occur except for any Technical Glitch or Technical/Administration/Political issues from the ISP itself.But I have been facing this issue from 5 days before the expiry date...