Integrating Mixpanel for Event Tracking Across Two Websites

Hello, team! I am facing an issue while integrating mixpanel. Any suggestions would be helpful. Thank You There are two websites, A and B, both using Mixpanel. Website A has its users imported to B, so events are tracked on both platforms. Now, Mixpanel from website B needs to be integrated into A so that all tracking events are available in A’s Mixpanel as well. - Both Mixpanel projects use `user_id` as the email. - Website A implements Mixpanel tracking server-side, while website B handles it on the frontend. - The Merge feature is already enabled in the project settings. - Setting `distinct_id` isn't working on A (server-side); instead, it replaces all previous IDs instead of merging them. How can the events be properly merged across both websites in Mixpanel?