Caution - The transmission 'P' lock mechanism is abnormal. Park your car at a flat place, and apply

Never made a post no here but I'm at a last-ditch effort to figure out what's wrong. So I recently had this problem where if it got too cold I would get an error message that said "Caution - The transmission 'P' lock mechanism is abnormal. Park your car at a flat place, and apply the parking brake completely" The first time it happened It was about 12 degrees out but the battery was old and I'll be honest I gave up because I got too frustrated trying to figure it out. Anyway after about 6ish hours I went back out and it warmed up to about 45-50 degrees.

I see that the 12v battery is dead so I jump it with my dad's car. There were some issues the first time I turned it on. I didn't have a dashboard at first but when I turned it back off and then back on it seemingly fixed after I had driven it around the neighborhood. Well since it got fixed I didn't get a new battery. Last week It was once again pretty cold (about 5 degrees this time) but I had parked in the garage to hopefully preserve it lol. I had wanted to start the car to warm up while I finished getting ready to leave so after maybe 4 minutes went by I went back out to leave but as I went to put it into reverse I got the same message again. This time I wasn't able to give it a jump so I was SOL.

A couple of days went by before I was able to work on it so I assumed it was the 12v battery again and had a buddy jump-start it but now I keep getting the same message. I had assumed that the battery finally gave out so I bought a different battery (that was a whole mess but I got the right one finally) I am now reading 12.2ish volts in "on" mode. The only problem is that the engine won't turn over and the parking brake on the transmission won't release to go into neutral so I'm not able to get it towed out of the garage.

I got a code reader then I got two different codes. P0A09 and P3102 however the code for P0A09 I've had since I've gotten the car because it was a pricey repair and the car still ran seemingly fine (I guess it could be my downfall lol). The other code P3102 says it is the transmission control ECU so I went and pulled it out but it looked fine. the wire that's connected to it looks fine but I'm not sure what the issue could be. A fix was to check the P CON fuze under the hood but it was fine. I also read that running a wire from the P CON fuze to another wire would help it. I figured that since a lot of people said it fixed said issue it would fix mine. It didn't.

I did some research and It could be an actuator on the transmission or a transmission pawl. someone else said that it could be the neutral and park switch. I no longer have a working cigarette lighter and the car used to beep if the key was in the ignition and the door was open but now if it's off and the car will beep to close the doors. so I don't really know why it seemingly switched but I figured I'd try to include as many details as I could remember.

its a 2005 Toyota Prius and I don't have a OBD2 reader that is compatible with Dr.Prius. I have not been able to drive it since getting the new battery, the new battery has been getting charged by a trickle charger for 2 days and I bought new terminals to ensure a good connection. The terminals are tight and I tested the voltage via a Multimeter of 12.5 volts and the car says a voltage of 12.4 volts. Any help is welcome and sorry if the post is confusing.