Zoho on my Desktop will not send SMS Verification text

Zoho on my Desktop will not send SMS Verification text

I have Zoho on a desktop and a laptop. I'm writing this from my laptop because I cannot login on my desktop. I enter my username, then password. Zoho then asks me to the the OTP that it has sent to my phone.  That SMS text never arrives on my phone.  I have already verified with my phone carrier that it in NOT in their end. Help please !!!!!  I need this format to work as I use it for my job.