Source
Create and manage offers
Providers can create both standard and private offers. Standard offers are displayed in the pricing section of a listing.
FAQ: Why am I getting error 'value <tag value> is not allowed by the specified allowed_values for tag <tag name>' when I am trying to assign a tag to the object? OR How do I set tag to null/default value after dropping all the allowed values?
You added possible allowed values in a tag that can be assigned to the tag when it is set on the object and then you dropped all these allowed values from the tag.
DROP <object>
Removes the specified object from the system.