How do I merge two calls at once?

[postal]

why wont my new iphone 6s+ allow me to merge 2 calls together?

[vzw_customer_support]

Making conference calls is a very useful feature, postal. Your phone is certainly capable of doing this. Please visit the link below, and click on the Making A Conference Call link for instructions.
http://spr.ly/6580BZTBw

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[SuzyQ · Accepted solution]

You can, but you need to be the initiator of both calls.  If someone calls you, that call can't be merged, by you, to another call.