Changing skins to any custom skin just gives you the last custom skin you used

So, every time I've tried to switch my custom skin to another custom skin, it just sets it to the same skin I just had on. Like, let's say I had a frog skin, and I wanted to change it to a knight skin. So I go through the process of selecting the image I want to use as my skin. But when I confirm the skin, when it asks what model type I want, it would show the frog skin again! I just don't get it. I've noticed many others have the same problem, too. I am able to change custom skins, but to do so means I have to change to a Steve skin, then select my custom skin, get the correct model type, and then exit Minecraft. Once I reopen MCPE my skin shows up. It's still irritating for role playing and such. If you have any idea what's causing this, then any help would be greatly appreciated. Thanks!