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I'm afraid that I can't help much as my technical knowledge is less than basic, but from other cases I read in the past the most probable answer is that your pc was already infected when you created the seed.
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Even if the PC is infected, a seed generated by a hardwallet cannot be exposed, since it was generated on the device itself, offline
To the OP
I saw that you started your wallets in 2022, and it was only in 2023 that this balance was moved, which following logic, must not have been a hack at the time of creating your wallet but something later, since a hack would make the transfer at the same time as it had access to your wallet
The most likely hypothesis is that your seed was exposed.
There's no chance that someone had access to your seed in the safe?
Could someone have managed to access it?
Where did you buy your Ledger?