How to use an external wallet

I’m a newby to BTC and Bisq so probably I’m doing something stupid here, but this is what’s happening.

In Bisq (not BisqEasy) I selected an offer to sell BTC (i.e. I am buying). On the next page it shows the details of the trade. I press the NEXT STEP button and it shows the details of the trading fees, deposit, etc.

I want to use my external wallet (Ledger Nano) so I press the button OPEN YOUR EXTERNAL WALLET FOR FUNDING. I immediately get a popup that says “Failed to open URI. ‘bitcoin: *******very long uri *****’ . The specified location is not supported”

I thought maybe that happened because I wasn’t logged into the Nano. But I got the same result after logging in.

So, do I need to do something in the Nano first before I press that external wallet button? Or what?

Thanks

That link should work if you have the ledger companion application installed on the pc, so that will intercept the link and then prompt you further to act on the nano to sign the payment transaction. If you don’t, then I suggest you still follow ledger’s guides to connect it to another wallet.
I wouldn’t personally use ledger software (nor ledger at all, actually, but it’s too late for that in your case), so I suggest you install Sparrow wallet, and then configure a wallet on it connecting to your Nano. Then go from there.
This specific topic goes past the scopes of this forum but I bet you can find plenty of guides on the internet for “load ledger nano wallet on sparrow” or something like that