Can't post ads on Craigslist due to the need for the verification code from an American phone number

I need your help guys. So client ask me to post Ads on Craigslist, but I can't because CRaigslist needs to verify the US phone number, I told this to the client but he wants me to find a work aroun which I did, guys, free phone numbers for online verification cases do not enter craigslist verification code or others like voip numbers not accepted by craigslist.

Maybe you can help me find out what other ways to do this so that I can post Ads to CL.

Many thanks guys for answering and helping out.