Well along with some others on here I too have had issues with Nougat, since it's update a few days ago I've had no wifi calling option. I've checked all the menus, cleared the cache and even gone for the full reset option (dramatic I know but needs must!!). Anyway long four days short finally my network provider, Three, contacted Samsung again on my behalf (I tried and failed yesterday) and they have now admitted that with some handsets there is an issue and they are working on a patch which should be rolled out soon, no release date as yet though. Anyway thought I should share the news with you guys 
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