connecting two different airpod gen 1 from different cases together

i have two generation 1 airpod cases. One case has a left air pod and the other gone, another case with just the right airpod and the left one gone. i was thinking since there are both the same generation of airpods then they could connect together. so i put the right airpod from the other case into the case with just my left airpod in it. Once i did that the little light started flashing red. I searched what i should do and it said to press the button at the back until the light turns white. They said it would make the two connect. It came up with the connecting bit down the bottom of my phone so i went through the process and it connected so i put both of the airpods in my ear. i played music and only the left once played. i have tried searching/ watching videos to see if it would connect but they all say to just press the button at the back of the case. I don't know if i should just give up and buy a new airpods case or just live with only using one airpod.