Hello, Kizurt.
Thank you for visiting Apple Support Communities.
I understand that some features are missing on a user account on your Mac after an update. Can you check to make sure her login information for iMessage and Continuity are enabled? Below are a couple troubleshooting articles for reference.
Messages helps you chat instantly
Get help using Continuity with your iOS device or your Mac
I would next make sure that audio and Video chat are enabled in Messages. You can check this by selecting Video in the menu bar and see if there is a check mark by these features.
When you disable video chat, you can’t start video chats, but you can receive video chat requests. If audio chat is enabled, the person you video chat with can hear you but can’t see you. If audio chat is disabled, the person you video chat with can’t see or hear you.
Choose Video > Video Chat Enabled.
When video chat is enabled, there’s a checkmark next to the menu item.
Messages: Start a video chat
When you disable audio chat, you can’t start audio chats, but you can receive audio chat requests. The person you audio chat with can’t hear you, but you can hear him or her.
Choose Video > Audio Chat Enabled.
When audio chat is enabled, there’s a checkmark next to the menu item.
Messages: Start an audio chat
If these do not resolve the issue, please let me know.
Cheers