Re: Advice please -Adding new Ledger Nano S Plus /Bitcoin??
Anyone advise please?
Yes, you should STOP using ledger devices and wasting money on them and on other closed source hardware wallets 
Learn something from bad examples of Tangem wallet.
Do I need to switch all BTC to Native Segwit?
No you don't need to do it.New address format starting with bc1 can help save on transaction fees, but you can continue using older format staring with 3 if you want.
Just googled Tandem and the problem they had had here.
Is this what you are referring to?
Seems like something I would never use tbh.
-https://tangem.com/en/blog/post/tangem-resolves-log-issue/
I ONLY use my ledger via an old laptop basic witu protection that is only used for transactions coupled to ledger.
Why suggest to STOP using?
Surely akin to a paper wallet but with further encryption.
Cheers