Latitude 5511 - Linux partition is gone

Hi,

I had Debian 12 installed alongside Windows. I used it for a few weeks.
Something happened. I do not know what. But my Linux partition is gone.

When I boot into Linux I only see the USB Live partition

When I boot into Windows I see all partitions.

I once got an error message like this.

How can I fix the problem?
Ask for your help