Named baby before gender now unsure

My partner and I had discussed names ONE time and the very first name I said out loud, he about broke his neck lookin at me saying “that’s the one I like too!” So our immediate agreement made us both excited about the name. This is our third child. The first is a boy, second is a girl both with the initials MMW. I wanted to keep the double M first and middle name. We agreed on “Monty” whether it was a boy or girl. Thinking full name Montgomery (it sounds cool with the last name) but we found out yesterday we’re having another girl and suddenly I’m not in love with “Monty”. I like the uniqueness for a girls name but I’m still unsure. My partner still likes it, but isn’t crazy about “Montgomery”. Are there any other names to be shortened to “Monty”? Clearly not worried about boy/girl names. AND totally open to a whole new M name altogether! Thank you in advance friends ☺️

Update: my list is now -Millie/Milly -Marlee/Marley -Malorie/Mallory/Malarie -Molly/Mollie -Murphy (although I know Dad will veto that one) -Muna (unsure of this one??)

Middle name is Mae!