Are you trying to activate your call forwarding through T-Mobile but the activation codes keep failing? This may be due to a recent change T-Mobile has made to your system that prioritizes cellular calling over WiFi calling.
Follow these steps to correct this error and activate your call forwarding to YouMail:
- Turn off your WiFi calling through your phone's settings
- Go to your My Phones menu and click Setup Phone to get the activation codes
- Dial the codes one at a time as shown
- If the codes fail, dial them gain until it succeeds. T-Mobile tends to drop calls if your network connection is weak
If you are still unable to activate your call forwarding, you may need to contact T-Mobile's technical support team and have them manually set up your Conditional Call Forwarding to your YouMail deposit number which can be found in the My Phones menu under the section How YouMail Works.
T-Mobile MMI Error Issue:
As of October 16, 2019, we've found that some T-Mobile YouMail users are experiencing an MMI error. If you received a message that said "invalid MMI codes" please follow the following steps.
- Go to your iPhone's Settings app
- Go to "Cellular"
- Click "Cellular Data Options"
- Tap "Enable LTE"
- Click "Off"
- Return to the YouMail app and try to reactivate (open the app, select the Settings icon in the bottom right, click "Activate" and follow steps).
- Go to your Android's Settings
- Select "Network and Internet"
- Select "Mobile Network"
- Turn off "Enhanced 4G LTE Mode"
- Return to the YouMail app and try to reactivate (open the app, tap the Menu in the top left corner, go to Settings, click Activate/Deactivate and follow steps).
**Note: The settings choices may differ slightly depending on the phone and OS.**