PhoneFusion

The invalid MMI code error comes from your carrier when the call forwarding codes in the app are dialed. It is most likely because the codes are not recognized by your carrier.

Our app uses standard GSM forwarding codes. Some carrier , at times, kick those back. You can choose to manually forward your no answer, busy and unavailable calls to us but you would need to confirm what codes your specific carrier uses. Here is a general reference of call forwarding codes that may help:

https://en.wikipedia.org/wiki/Call_forwarding

The number you would forward to is 8132000200.