asus-me176c rootFS flash error

I have followed the pmOS guide https://wiki.postmarketos.org/wiki/ASUS_MeMO_Pad_7_(asus-me176c) to get pmOS on my MeMo pad 7. The ESP flashes fine and I can boot stock android, and TWRP through it. But when I go to install the RootFS I get this error

• reuben@fatso ~ % fastboot flash data asus-me176c.img
• Invalid sparse file format at header magic
• Sending sparse 'data' 1/2 (513219 KB) OKAY [ 12.676s]
• Writing 'data' FAILED (remote: 'flash_cmds error!')
• fastboot: error: Command failed
• reuben@fatso ~ %

Any help is appreciated!

Reuben