Sorry that this is causing some confusion...
Couple of things:
1) There is no need to use the DIGITS app when you have a duplicate SIM in your device (so feel free to remove the application)
2) Not sure why the Huawei is trying to route the call to the DIGITS app, since you definitely don't need to do that either. Doing #1 should definitely eliminate #2 from happening. Though if you're using the DIGITS app since you want to have access to yet different set of numbers, then there is likely a setting somewhere in the Huawei's settings to tell it that the native dialer is the main app and not to prompt for using a different app - however I"m not sure about that.
Please let us know what you find out.
Thanks for helping us improve DIGITS!
Thanks! From speaking to a couple representatives, I thought that the DIGITS app was needed for the duplicate-SIM device.