Conventional Pull Form Help

I’ve been pulling sumo for about a year and a half my max pull with gear has only moved about 10 pounds(420). So I decided to go back to conventional where my raw pull was 410. I took video of my first pulls yesterday. The weight was light but I notice slight rounding in my back when the weight came off the floor but it snapped back after that. I posted this video to see if anyone can shed some light on what to fix on my conventional to get my form to where it needs to be. I know my pull is complete shit and needs to get better and stronger. Thanks everyone.

side note, i’ve tried getting this to upload the video from my profile numerous times and it times me out over and over. Any ideas on how to get this to work so you all can see the video?