Vertical holes inside the print

This is a perfectly round object- half of a sphere. Confidentiality clause doesn’t allow me to show the full object.

Still. This is on one side of the object. The rest is perfectly round. The problem starts from the top down to the printing bed. Any ideas?

Maybe extrude gear slipping? I'd check nozzle for clog first, then extruder gear.  Also the part looks like you might be able to spiral mode on it; no seam in spiral mode so maybe print without the problem showing.

Looks to be happening on the seam. I agree with Pasta, check nozzle. Maybe even clean out the feed tube.

This is a perfectly round object- half of a sphere. Confidentiality clause doesn't allow me to show the full object.

Still. This is on one side of the object. The rest is perfectly round. The problem starts from the top down to the printing bed. Any ideas?

you can share STL / ZCODE with me through PM, it stays with Zortrax :)