[DAX] FORMAT Month not working properly

I'm having an issue where the FORMAT function for Month is only returning January and December. I originally tried:

SHIP MONTH = format(month('Table'[DATE]), "MMMM")

and was only getting January and December. Then I decided to split the operation. I created a column:

SHIP MONTH NUMBER = month('Table'[DATE])

which produced the correct month numbers for the corresponding dates. I then created:

SHIP MONTH NAME = format('Table'[SHIP MONTH NUMBER], "MMMM")

but alas, I am still getting only January and December. Any ideas on what I am doing wrong here? I don't use FORMAT often, but I feel like my syntax is correct. Thanks in advance for any and all help!