Neatsfoot oil on the bend, let it sit and soak in for a week before hanging, if after the week it feels supple(ish), give it more nfo all over and hang it without any weight, give that another week, again, repeat with the nfo and see if everything is softening up nicely, if there is still a bend or groove try a 2 oz weight to give it a wee pull, always try very little and over a long time, it can fix a very dry strop doing it right or it can kill it doing it wrong, I sorted a very dry vtg Russia shell strop from something that felt like a stick and would break/snap if I tried to bend it, it is now my go to strop, and has great colour and suppleness, slowly...slowly if you really want to keep it, it will last for many years if done right...or it will end up in the bin if you have no patience....good luck, i'm sure you will pick well, vtg strops are awsome.