How do I inform the Landesamt that I lost my job?

Hi! My boss just informed me my contract won't be extended. I have a working visa that expires with the contract. I already informed the Agentur für Arbeit and know that I have to inform the Landesamt but, with the new online forms, I'm a bit lost. With which online form do I contact them? Should I just apply for a job seeking visa? Or just use the emergency contact form?

Thank you for your help!