Internal transfer from full time to flex PT

So my warehouse just dropped a flexpt option, my kids have winter break coming up so I switched to have more flexibility. I started on 12/1 with a training day for 4 hours. I assumed it would be training on how to pick up shifts, when shifts would drop, and changes in benefits. I showed up and first they tried to send me to outbound, my transfer was for ib and since I'm not trained in ob they sent me back to learning. Go back to learning they decide they are going to cross train me in dock ( I am trained in prep). The 4 hours wasn't enough time to finish the training so they told me to clock out and continue on my next shift. Now my problem is there are 0 shifts for the week. I emailed hr and they responded that when I come on next shift to have hr help me schedule shifts... there are 0 shifts! What should I do? Wait and see if they drop shifts at some point? Go down and talk to hr? Anyone else have these problems? Any advice would be greatly appreciated! I wanted flexibility but not 0 shift!

Eta: HR emailed me and told me basically they don't know how to add shifts for flex, so just email what shifts I want, and they will add them until they get it figured out. We are a new building (less than 6 months) and they just opened up the flex shift so I'll give them some grace for now.