Please upgrade to 3.5.19 and run the below commands in SSH as root to regenerate the graphs.
cd /usr/share/nginx/spotipo source .env/bin/activate python manage.py rebuild_monthly_stats
@Tahir-Pervez It is possible to have multiple VZ to talk to Spotipo. Just add another entry in the SZ table. External Ip adress is not used anywhere. Communication always happens between VZ -> Spotipo. Hence there is no need to have load balancing.
You can have multiple sites pointing to same vSZ. However, SZ doesn't allow multiple Radius servers with same IP. Hence while adding second site, use the custom password option and enter the password from previous site. ( I will reply to your mail as well now )