i do not know what caused the crash

bitcoin has 12-24 words as seed. but this is a different system than bitcoin. of course i kept the seed and thought i could restore using the seed. it is not possible. no one told me that. umbrel did not show the warning when i funded the node. only when i generated the seed umbrel told me that i had to save the seed words which i did of course.

lightning is a seperate network, has a seperate seed system, and it is centralized, has owners and 'management'. i find it very weird that now they even tell you that you can lose your money.