If this is a postpaid sim card, just visit the nearest Globe Store have them check your new sim card. As for prepaid LTE sim, this sims are pre-activated and no need to activate LTE all you need is LTE capable sim and LTE capable device. Now you need also to check the specification of your phone to know if the LTE frequency is supported by the model of your device. There are some mobile phones that are LTE capable but does not support Globe LTE frequency. Check your phone manual for the supported LTE Band make sure it is indicated that it supports LTE Band 3 1800Mhz.