Ensure Chrome and Edge, they are updated to the latest versions. Outdated browsers might have compatibility issues with Web WhatsApp.
Clear your browser's cache and cookies.
Try temporarily disabling all extensions and see if Web WhatsApp works.
Check your VM's firewall settings and see if any rules might be blocking connections to WhatsApp servers.
You can try connecting using a VPN set to a different location (check local regulations regarding VPN use).
Advanced Messaging for WhatsApp in Azure Communication Services