The data you provided for does not match the list of valid values (Size error)

Hi

I am uploading a flat file in the clothing category, it is a variation listing for SIZE.

The sizes that are in years such as 2-3Y, 3-4Y are uploading fine. However the sizes that are in months, 12-18M, 18-24 months are getting the following error:

The data you provided for [L9_0001 -1] does not match the list of valid values. Please select a valid value from the Data Definitions and resubmit.

It seems that whatever value I enter for the age_range_desciption and size_map result in this error when the value “12-18M” is added to size_name.

Any idea what I can type into the size_name field to avoid this error?