Unable to receive phone number verification message

[Imam Siraj]

Greetings, I have been unsuccessfully trying to add my phone number to my google account, as in thr verification code doesn't arrive. I have tried multiple times but the message doesn't arrive. I have contacted my ISP (Omantel - www.omantel.om) to check with them whether it's a technical issue on their side but also at the same time posting here hoping to get a solution.