Still too small? Worn about a month, no issues whatsoever, very comfortable. Foot fits better in the 41. Toes don't go over the edge. Walking is super easy. : r/Birkenstocks
The Birkenstock Buyer's Guide | Sizing, Fit & Care | allsole
Birkenstock Arizona Desert Khaki Narrow Footbed Sandal (Women) – Cook and Love Shoes