To ensure that SMS sending works as expected, format your mobile phone number in the E.164 international format (with a '+' and country code). 


Examples below:


Here are a few examples:

Country Local E.164
USA 415 555 2671 +14155552671
UK 020 7183 8750 +442071838750
China 021 6309 5246 +862163095246
Australia (08) 9287 8230 +61892878230