You’re using a text layer as a displacement map for itself and then try and turn it into a 3D layer.
There are at least two problems with that: Using the layer itself for displacement (I didn’t realize you can even do that) and, more problematically, using a 3D layer for displacement, when displacement is a 2D effect.
IF you want to displace the text by itself — which already seems pretty strange — you would to duplicate the text layer, precompose it with some sort of background (such as medium gray) and use the precomp as a displacement. More likely you don’t want to use the text but something different to displace it.
Kalleheikki Kannisto
Senior Graphic Designer