Why won’t my Macbook Pro identify it’s own battery?

Update: I’ve decided I’m giving up on what I have to work with, and I’m gonna buy a new battery.

I have a 13 inch MacBook Pro that I have been working on refurbishing, and I’ve run into an issue where if I unplug it from the charger it shuts down and it won’t show battery percentage. I think this might have something to do with when I was dusting out the insides of the computer and a misaligned flex cable, but I am really not sure. Here’s an image of white happens when I first turn on the computer:

i’m really at a loss as to what to do at this point, because I’ve just been scouring forums for the better part of a month.

Either the battery is not connected or it has failed.

Did you receive any messages about “service battery”?

You will likely be taking the cover off again to check.