Hello there, CoeLeigh.
It sounds like your volume buttons become unusable when your iPad is plugged in to charge. The following Knowledge Base offers a few good recommendations for troubleshooting issues of that nature:
Get help with buttons and switches on your iPhone, iPad, or iPod touch - Apple Support
On iPhone, the volume buttons and Ring/Silent switch are on the left side of the device. This image shows these buttons on iPhone 6. The buttons on other iPhone models are similar.
On iPad, the volume buttons and Side Switch are on the right side of the device:
If any of these buttons or switches aren't working, follow these steps. Test after each step:
- Unlock your device. Some buttons don't work from the Lock screen.
- Check for debris or dirt around the button or switch and clean it with a soft cloth.
- Remove all protective films and cases that might interfere with the button or switch.
If the button or switch still isn't working, if it works intermittently, or if it's damaged, contact Apple Supportto set up service.
Thanks for reaching out to Apple Support Communities.
Cheers.