2006 Prius both key fobs not working

Hello friends,
I purchased 2006 Prius recently. First time owning a Prius.
I had a low battery in one of the key fobs. So I replaced it with new one. At the same time, I also replaced the battery on the other key fob as well.
Now none of these key fobs are starting the car.
The car's battery is good. 12V battery was also showing full green on the display before I decided to replace key fob batteries after reaching home.
As of now, I get no lights on the dashboard - not even door open/close indicator.
I tried resetting the Key button and also what I read somewhere as a 'chicken dance'.
Nothing.
Also tried inserting the key fob in the slot and pressing the power button. The led on the power button glows green. Park button led is green. But nothing on the dashboard.
If I press open or close button on the keyfob I can hear a small beep coming from the car.
When I press open button when sitting inside the car, I see some fluttering of left green arrow for 2 seconds.

As I mentioned, I am very new to Prius. I searched the forum for similar problems and did bunch of fiddling around as some of you recommended - all from inside the car.

I would appreciate any pointers that you may provide.

Please, please help!

RSP

 

Thank you ToyotaGal for the response. These are the brand new, freshly purchased - Energizer CR2032 batteries that I put in the key fob. The batteries are inserted correctly. Red LED on the key fob glows when I press either of Open or Close buttons on the keyfob.

 

Thank you mr_guy_mann for your response.

The 12V battery is relatively new. I had been driving the car for a few days and the battery gauge on the center screen always used to show 12V battery charging after a few minutes of driving to a green color bars (filling almost 90%). The 12V battery was showing up as almost 90% filled with Green color on the battery gauge on the center screen before I parked & switched off the car- and then - immediately thereafter I replaced the batteries in both the key fobs. Right thereafter, I went on to start the car just to make sure that the newly inserted batteries work. Unfortunately, both the keyfobs stopped working - since I replaced batteries in both of them at the same time.
Thereafter, I bought another fresh pair of CR2032 batteries from the store - and then replaced them in the keyfobs.
No luck.
None of the keyfobs are working.
The LED on the keyfob does glow to red when I click on the open or close button.