luks encryption passphrase fails if dock is connected

If my ThinkPad P1 gen4 is connected to Lenovo Thunderbolt4-dock (0B40 series). I'm not able to start. My root- and home-partitions are encrypted with luks. At boot I'm asked for passphrase, for decrypting root-partition. This works if it is not attached to dock. If it is connected, after I wrote passphrase, but I get

`
no key available with this passphrase

` Why the dock is blocking decrypting partition?