URGENT! Cannot send sms by http2sms service

Hi
I have create API USER
LOGIN = INVIOSMS
PASSWORD = xxxxyyyy

I have create SENDERS
OFFICINA

My NUMBER is
00393391915793

The url should be

https://www.ovh.com/cgi-bin/sms/http2sms.cgi?&account=sms-rr495xxx-1&login=INVIOSMS&password=xxxyyy&from=OFFICINA&to=003391915xxx&message=MESSAGGIO

but it not work. Error come back is:
KO
Following receivers phone number are invalid : "+3391915xxx"
but number is correct

I must create also receiver number list in your account?
NOTE
seem that it not work with chrome …

Are you sure you used 003391915xxx and not +3391915xxx as the phone number?

Also, the number 003391915xxx does not match your number 00393391915793, looks like you have omitted some digits?