I am trying to pick first break arrivals in Zero Offset VSP on the Crewes toolbox and another software. My problem is that I start picking from 4th trace because I cannot see the first three traces when I look at my data, which results in wrong velocities.

My data is passive zero-offset VSP data, utilizing ambient noise sources. I created this by using a modeling code.

I added one of my data and the problem's screenshot

Can I fix this on Seismic Unix?