Could you give us a bit more information about how (or when) this started happening?
Is everything related to your nano s up to date?
Check if your software is at least this version or newer:
- Ledger Wallet Bitcoin Chrome app: v1.9.10
- Nano S firmware: v1.3.1
What exactly happens when you open the BTC Wallet chrome app and plug in your nano s? Does it try to verify the authenticity of your nano s? Or doesn't it even recognize you plugged in your device?
Is this the first time you are trying to open your wallets or did it just stop working someday? (This is a crucial point to understand your problem better)
It also would be nice to know where you bought your nano s. From their website, amazon, reseller ?
If its not reacting to the nano s being plugged in at all:
Did you already try it out on more than just one pc? Are you sure the USB-Port is working?
You could try an USB-port which is sitting 'directly on the mainboard'. Not the front-side ports and without any additional cables/extensions.
If there is an error message displayed it would be pretty useful to see a screenshot or getting any further information about your error.