The pkgbase.freebsd.org URL is being changed to pkg.freebsd.org to match existing infrastructure for 15.0-RELEASE. This requires a number of moving parts to be tidied up over the coming weeks.
As of today, DNS requests for pkgbase.FreeBSD.org are replied with an empty response for A, AAAA and any. That breaks installation of 15.0-RELEASE and I guess because this is an empty response versus an NXDOMAIN, fetch just shows "No error", which is not very informative. See bug #291255
(In reply to Vassili Tchersky from comment #1) bug #291483 sorry