Hi Remya
I advise you to look only at the "official" publication page for Open APIs: https://www.tmforum.org/oda/open-apis/table
In the official swagger for TMF620 (available on this page), all catalog entities, including ProductSpecification, have POST for creation. The user guide shows examples of how to POST and PATCH catalog entities.
Hope it helps.
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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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