Apple Notes tags randomly disappear and are replaced with "#..."

Tags in Apple Notes randomly disappear... And are replaced with "#..."

What causes this?

Tags that are added to notes just disappear and display as "#..."

Some times multiple tags in one note. The notes remain intact; only the tags are modified.

Logic would tell me it is a result of me deleting a tag, but I haven't deleted any.

Happens across all devices and all devices are running the current OS.