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I had my mesh mirrored correctly at first but then I decided to work on the hand in a different layer (Two) and then copy past it back to layer 1. I then selected both meshes and pressed Ctrl+J to merge the 2 into 1 in object mode. However I forgot to apply the mirror modifier before merging the 2 (not that I thought that would matter) and the mirror modifier disappeared so I go on to connect the hand to the arm in edit mode change back to object mode select all and add another mirror modifier.
Top view of when morring Y axis:
I've tried all Axis and they all seem to be mirroring weirdly in a diagonal fashion.
Things I've tried already
I've selected all vertices that run along the center from top to bottom on the Z axis then Pressed Shift+S and selected "Cursor To Selected" followed by Shift+Ctrl+Alt+C selected "Origin to 3D Cursor" and still have the same results.