Hi,
The /ContactPerson/ you are referring to is the summary view of activities.
The summary view of activities displays records related to activities on the timeline.
For example.
This email is associated with a contact.
This email shows a record of the relevant contact on the timeline.
Activity has the regarding set to an Opportunity, Quote, Order, Invoice, Case and Contract, a limited list of OOB entities.
If you want to display these records on the activity records of the timeline.
For example, displaying related contact records requires a 1:N entity relationship between the current entity and the contact.
However, the relationship between the Work Order entity and the Contact entity is N:1.
Therefore, the activity records of the timeline in the Work Order entity cannot show the related contact records.
If my answer was helpful, please click Like, and if it solved your problem, please mark it as verified to help other community members find more.
If you have further questions, please feel free to contact me .
Best Regards,
Dengliang Li