Add FAQ & Troubleshooting (#4630)

* Add FAQ & Troubleshooting

* Apply suggestions from code review

Co-authored-by: forstisabella <[email protected]>

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Co-authored-by: markzegarelli <[email protected]>
Co-authored-by: forstisabella <[email protected]>

Author: 3 people

src/connections/destinations/catalog/actions-mixpanel/index.md

@@ -128,3 +128,10 @@ If you want to confirm, you can configure the new destination to point to a diff
 > Contact Mixpanel support if you find features missing from the Mixpanel (Actions) destination that were available in the classic Mixpanel destination.
 
 {% include components/actions-map-table.html name="mixpanel" %}
+
+## Troubleshooting
+
+### Track events are not attributed to Mixpanel Groups
+
+Ensure that the mapping(s) handling your `track` events have the field for **Group ID** mapped to a valid value. By default, this field is mapped to the event variable `context.groupId`.
+