I received a text message from 650-305-0297 that read

"Thanks 4 Visiting Our Website Call 800-571-4835 To Claim Your $200 Walmart Voucher! Reply STOP 2 Unsub or Call 415-513-5459 2 Unsub Now"

I called the 650 and 415 numbers and I think they are cell phones, because I got the message "mailbox is full". Calling the 800 number you will get a company claiming to have information on walmart vouchers. The actual unsubscribe number given to me by this company is 800-440-9757. Hope this helps.