Good day angelyoong09, what device are you currently using?
Some factors that contribute to that problem may be as follows:
1. Signal strength of the place you're in.
2. Your device is not set to HSDPA (may be turned off on your phone).
The second option can be addressed through your settings. Turning the 3G/LTE/HSDPA on may solve your problem.
acbalaga is correct try to do those basic troubleshooting if you have done that before. have you recieve sms from globe that you reach 1GB data cap per day? or if you havnt. call the hotline Contact Us so that they can check your account if you reach 1GB.
We're all supposed to have an unlimited internet, unfurtunetly Telco Company around the world has been stop providing un unli net to their subscribers due to heavy users that affect internet quality. so they set a data cap for each one of us even though we are paying 5,000+++ monthly. so we just need to accept the changes. no more unlimited internet.