Why are my AirPods not pairing together?

My AirPods came to me brand new about 2 years ago and have not been replaced. Sometimes after they have charged for around 15-30 minutes to use, they both have ANC abilities, but when clicked, it only changes the bud that the click came from. They have to be inserted back into the case and do a bunch of random stuff to fix it. Is there a way to fix it so it is not a hassle every time I use my AirPods?

Also, I read that some first-generation AirPods can have a problem with their noise canceling and pairing, just wanted to point it out.