Bohan Dixon missed the chance to put Warrington ahead when Jonathan Brown denied him from the penalty spot after Ben Garrity was brought down in the box, writes Josh Holland.
The visitors took the lead 10 minutes into the second-half when Tony Gray slotted the ball past Brown after being played through by Dylan Vassallo.
Charles was brought on for Jaiden White just after the hour mark and it took five minutes for the hosts to equalise when the ball reached the forward who fired the ball onto the crossbar and into the net.
Stafford took the lead moments later when Bradley Grayson directed Danie Hawkins effort past Anthony McMillan.
Warrington thought they had drew level when Mark Roberts tapped the ball into the net after Jack Dunn’s free-kick hit the post.
However, the Warrington captain was judged to be offside.
The equalising goal came from substitute Amis. After Stafford failed to deal with Garrity’s hopeful header.
Amis latched onto the ball before lifting it over Brown to save Warrington from their second league defeat of the season.