WANDF For Spirit Airlines Personal Item Bag 18x14x8 Travel Duffel Bag Underseat Foldable Carry-on Luggage for Women

Also sharing if you haven't found one already: https://www.amazon.com/dp/B09SDC861T?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_3

This is the one my partner and I use if you haven't found one already: https://www.amazon.com/dp/B09SDC861T?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_3 . Fits everything you need. I recommend using tote/plastic bags (or if you're fancy, those zippable pouches) to maximize space and have some semblance of organization. Makes it so much easier to fit what you need imo.