The case is the following I am using a Nekroz Kaleidoscope ritual to summon Nekroz of unicore by sending Herald of the arc light.

Soon after using the spell field Ritual Sanctuary, even having more than four magic cards simply can not revive it.

Could someone explain why?
You can only summon an Extra deck monster from a location other than the Extra Deck if it was properly summoned, since Herald was never synchro summoned you cannot summon it with Sanctuary.
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