Startup errors for health check on deleted repositories

In one of our Nexus instances, using the Web GUI, I deleted several Repositories and BLOB stores. After each deletion, I received the green pop-up message “Repository deleted” or “Blobstore deleted”. Next, I restarted the Nexus service. I see many errors in the nexus.log file similar to this, and referring to the Repositories that I deleted:

2020-10-02 14:37:24,595+0200 WARN  [healthcheck-tasks-10-thread-1]  *SYSTEM 
com.sonatype.nexus.plugins.healthcheck.service.impl.HealthCheckTaskManagerImpl - 
Unable to unsubscribe health check for repository my-repo
javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX 
path building failed: sun.security.provider.certpath.SunCertPathBuilderException: 
unable to find valid certification path to requested target

Since the repositories are already deleted, I can no longer use the GUI to disable these health checks.

Can anyone advise how I can get rid of the obsolete references to the deleted repositories so that our nexus.log file is not littered with these errors?

Many Thanks,
Janet