I have a model T.
I have already set up my shamir backup (5 word-lists, necessary number to recover:2)
I want to know if i can reset my shamir backup settings? For example, number of word-lists and necessary number of word-lists to recover the wallet? thanks
It is technically possible, but not on a Trezor device.
You would need to import your Shamir seed into some sort of 3rd party tool, decode the master secret, and then re-encode it as a different set of shares.
(I will not be providing any links, because I cannot guarantee that they are safe. But if you are interested, search for “SLIP-39”, the Shamir standard. The usual caveats apply: you should never enter your seed into a PC, so if you want to do it anyway, it is completely up to you to figure out if/how to do it securely.)
Note that doing this does not invalidate the previous set. If someone finds 2 of the old shares, they will be able to access your wallet. If that is something you are worried about, you will need to create a completely new wallet and transfer your funds to it.
(A moderately experienced programmer could relatively easily modify a Trezor firmware to do it. You would then build the custom firmware, click through the “this is not secure” warning, recover your seed, and regenerate the shares.)
ok thanks, so the solution is to create another wallet, I though the seed keys are associated to the hardware.