When you freeze TRX you have to wait 72 hours before you can unfreeze them. After 72 hours, you can instantly unfreeze your TRX any time as follows:
Tap on TRX token from your Portfolio screen, then switch to the target Account.
Inside the TRX Account, tap on FREEZE icon.
Inside Freezing screen, tap on Unfreeze button.
Switch between BANDWIDTH and ENERGY tabs, then tap on the TRX amount you want to unfreeze. Once the amount of TRX marked with a green check mark, tap on the Unfreeze button.
NOTE: If you have frozen TRX for bandwidth (resp. energy) you will find the TRX amount listed under BANDWIDTH (resp. ENERGY) tab.
In the next screen, you can review all the details of the transaction before tapping on Submit Transaction button. After that, enter your PIN code to sign the transaction and you are done.