Shamir Backup Reset

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.)

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ok thanks, so the solution is to create another wallet, I though the seed keys are associated to the hardware.