Hi Anuradha
Apologies for the belated answer, hope it is still helpful.
ContactMedium is a utility entity that is attached to a wide variety of entities in the Open API data model. The Customer entity is one of these, as you can see in TMF629 Customer Management. So yes, you can use the ContactMedium on the Customer.
If you feel the need to have contact medium directly on the trouble ticket itself (TMF621), you can of course extend the Open API model (as per the guidelines in TMF630) and add it there.
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Jonathan Goldberg
Amdocs Management Limited
Any opinions and statements made by me on this forum are purely personal, and do not necessarily reflect the position of the TM Forum or my employer.
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