Hello David
Did you remove them on the probe server?
Usually by accessing https://<proveserver>:8443
https://docs.hitachivantara.com/r/en-us/ops-center-analyzer/11.0.x/mk-99ana001/changing-ops-center-analyzer-system-settings/managing-the-analyzer-detail-view-server-and-the-analyzer-probe-server/deleting-probes