I replaced the damaged lightning port and it still won’t charge.

A few months ago the lightning cable broke off while plugged into my iPad. I was able to remove the broken piece, but damaged one of the iPad’s lighting port pins in the process. So I ordered a new lightning connector and adhesive strip set form ifixit. I’ve replaced a few iPad screens before with success so I figured this repair would be no problem.

Well I finally got around to doing to repair, and it did go smoothly. I decided to stop the assembly just before removing the backing strips from the adhesive, but still placed the touch panel in place and tested the charging. And I’m glad I did because it doesn’t work. I left it plugged into two different known good chargers and cables. Each for several hours and overnight. One was an older 10W iPad charging block (model A1357). And the other was a newer USB C charger from an iPhone (model A1720). All I get when I press the top button is the flashing red low battery symbol and lightning cable image with a lightning bolt above it for a few seconds.

Because the screen isn’t glued down yet, I could easily open it again to double check all the connections. Everything looks good to me.

Any ideas what to try next?