I've tried "+382" and "+381" (Montenegro and Serbia) and it remains set to +1 (USA). When I tried with +34 or +43, it worked ok (Spain and Austria). Can you please check that?
It is tested on android, with 1.9.2 version of Digits, and this way:
DigitsAuthConfig.Builder digitsAuthConfigBuilder = new DigitsAuthConfig.Builder()
The phone has Montenegro +382 SIM card, and is connected to its home network.