We have multi-select checkbox as a custom field and I had this Filter generated that worked for several months
Europe_Tenant_Migration is EMPTY OR Europe_Tenant_Migration != "Moved to CN1" AND Europe_Tenant_Migration != "Not Required"
For some reason this stopped working and this JQL is now returning all rows even if they have "Moved to CN1" as checked. I have tried to change it every which way and I can't get it to only display the ones where nothing is checked.