Managed Instance Group in Google Cloud stuck in failed state after deletion attempt

A few days ago, I attempted to delete an outdated instance group from the Google Cloud console / online interface, and since then, its been permanently stuck displaying a red circle with an exclamation mark (instead of a green circle with a check mark), and provides the error below when hovered over:

Operation type [compute.instanceGroupManagers.insert] failed with message "Invalid value for field 'resource.instanceTemplate': 'https://www.googleapis.com/compute/v1/projects/slope-social-deploy/global/instanceTemplates/slope-server-template'. InstanceTemplate should be usable in all selected zones."

I've attempted to delete it using gcloud commands as well, but it appears that since it's no longer associated with any zones, it can't be fully removed. It does not show up in lists of managed instance groups (MIGs) when I check them with gcloud commands, but it nevertheless remains visible and failed in the Instance Groups tab in the online console.

I've also cleared my browser cache to no avail.

I unfortunately don't have access to technical support through my current Google Cloud plan. Is there any way to resolve this?

Closing this question, as the Google Cloud Console / gcloud discrepancy managed to resolve itself on its own. Thank you again to all who answered.