That doesn’t look like the site specifically for TX. Not sure if there might be something that could cause another site to report an error.
Double check at
You’ll need to enter your TDL (Texas Driver’s License Number) and date of birth after clicking the “Am I Registered?” button
I was hoping you’d be able to find it.
Maybe you can contact your county registrar and see what happened. The deadline for voter registration for the presidential election was October 7. Maybe there’s something that can be done.