Can access website over WIFI but not with LTE on cell phone

Posting here in hopes of saving folks heartache. Had a new server with only one web site on it. Could access the web site fine over WIFI, but clients reported could not access on cell phone. On cell phone would get the SORRY Cpanel page. Turns out I had the DNS nameserver at linode.com A/AAAA records set with both IPv4 and IPv6 addresses. But has not added the IPv6 addresses to WHM and bound it to the web account. Cell phone LTE was using IPv6 and thus the "Sorry" cgi default page. Once I added the IPv6 to WHM and bound it to the web account. Problem solved! Hope this saves some folks some time in the future if they run into this. :-)