Home button trouble

Hello,

If the Home button doesn't respond

If the Home button doesn't respond when you press it, follow these steps:

1. Make sure that your iPhone is on.
2. Make sure that your hands are clean and dry.
3. Remove any case or protective film that covers the Home button.

Your iPhone uses capacitive sensing technology on both the Multi-Touch display and the Home button. You should be able to use the Home button with gloves that work with the display.

From:

About the Home button on iPhone 7 and iPhone 7 Plus - Apple Support

Okay that's what's from Apple's Website. I don't know exactly how the Home Button works, as I'm a user like you, and don't work for Apple. The case should be made specifically for the iPhone 7 Plus, and work with the Home Button. I am not sure how the cases work, as I haven't looked for a waterproof case for my iPhone 7 Plus. Have you tried contacting the case manufacture?