What does Matthias remember about Lena's last day before she disappeared?

Lena came to visit her parents the afternoon before she disappeared to have coffee with them. Her bicycle had been stolen from the campus, and Matthias had given her the money to buy a new one behind his wife's back. Karin thought that Lena needed to be more independent and get a job. That was the last time that Matthias and Karin saw their daughter.