aircrack-ng not capturing handshake even after deauthentication

I’m using Ubuntu 18.04. I had used Aircrack-ng before. I was trying to use Aircrack-ng to get a handshake from a router, but it’s not capturing the handshake.

I had also sent -0 deauth and the client was reconnected, but it didn’t capture the handshake. What can I do now?