Some SMS return with status: " Phone has blocked SMS"

I have an App that sends SMS messages through SNS service. The orientation number we put is an 11 digit Random number that starts with +1205. I mostly send messages to Ukraine and Israel but some of the messages I send to phones in israel returns with the status: "Phone has blocked SMS" (""smsType":"Transactional","providerResponse":"Phone has blocked SMS","dwellTimeMs":52,"dwellTimeMsUntilDeviceAck":273},"status":"FAILURE"). Its strange since my phone blocks does not get SMS from SNS service but my employee phone, same model gets SMS. I checked my phone to see is it filters messages or block SMSs and talked with my carrier and they said that the phone is not blocked. Thoughts anyone? Thanks, Ronen