I'm a frustrated and never ever will be Hotlink user.
Did you guys know, the hotlink number is 'terminated' upon the expiry date, you still can receive calls and sms for 14 days, but no longer able to top up and just wait for the number to disappear.
Digi has a 90 day 'cooling off' period, where if you top before the 90th day after the expiry date, you can still continue to use the line without forfeiting your balance.