Cannot Import Custom Skins

Summary:

When trying to import a custom made skin as a .PNG file, I get the "That's not a Minecraft skin, silly." error.

Steps to Reproduce:

1. Launch Minecraft for Android
2. Open Dressing Room
3. Tap Edit Character
4. Open Left Menu Options
5. Tap Classic Skins
6. Tap blank character under "OWNED SKINS"
7. Open Choose New Skin
8. Navigate to desired .PNG file and select it
9. Error Message shown

Observed Results:

The player can't change import custom made skins, and instead receives an error message.

Expected Results:

The skin should be imported, and able to be applied.

Screenshots/Videos Attached: Yes

Notes: I sent my skin file to a friend on my SMP that uses a Windows 10 PC, and they were able to import my skin without any issues.