Hello Zadanzadine,
Thank you for reaching out to Apple Support Communities.
These steps can help if your Silent Switch isn't working as expected:
"If a button or switch isn't working on your iPhone or iPad
If a button or switch isn't working on your iPhone or iPad, here are a few steps that might fix the issue. If they don't, you'll need to set up a repair.
- Remove any protective films or cases that might block the button or switch.
- Check for debris or dirt around the button or switch and clean with a soft cloth.
- If the button or switch still isn't working, is damaged, or works intermittently, you can set up a repair"
More details can be found here: If a button or switch isn't working on your iPhone or iPad
If the issue persists, it may be best to reach out to Apple directly.
You can do so by going to Get Support
They will take a closer look and check on available options.
Cheers!