On my six year old Trezor One I attempted to connect via Trezor Suite on my laptop. I updated the firmware, which went fine, then I realised that I had forgotten my pin. Since I have the 24 seeds written down on paper, I figured it would be fine to do a factory reset. As I tried again to start the new setup via Suite, I attempted twice to recover my seed. The message I get was:; Device recovery failed: Invalid seed. What can be the issue? How can I make sure they’re not lost? I also unfortunately remembered the pin after wiping the Trezor, but I guess that wouldn’t make any difference now. .
Most likely, you have not entered the seed words in the correct order. Make sure you always look at the Trezor screen to know what number word you are supposed to be entering.
If this fails and you are sure that you got the order right, it can happen that you wrote the words down wrong – the seed card is numbered, but it is easy to make the mistake of writing the words across instead of down or vice versa. In that case, try copying the words on a piece of paper with the numbers going in the other direction, and recover again.
Lastly, it is unlikely but possible that one or more of your words is written down with a mistake in it. You can go through the BIP-39 words and see if one of yours doesn’t have a similar looking option on the list.
(This process can be automated, but that means exposing your seed to the PC, and as such we cannot recommend it. Please do your own careful research if you decide to go this route.)