Have you contacted your supplier, and is the resin of the specifications that you requested?
There seems to be a problem of possibly a contaminant of a noncompatable resin present.
What are the temperatures for your process?
You might try to control the width by using a restrictor bar in the outside lip of the extruder and turn off the heats to the restricted zones to run a narrow sheet if the full width isn't required.
The time involved and the readjustment of the puddle can take some time, so it would only be...