Ok, let's try to be more helpful
There are times when air power is not working for you. The opponent has built up critical mass. They have the numbers. They have technical superiority. I've been in these situations. It's not easy. When this happens, you have 2 options.
1. Skip the propeller fighters on the Air tab. Go to the Secret tab and leapfrog the opponent with jet fighters. You are going to need a lot of rares, and high level secret plants, so this is not for poor countries. It helps if you have allies who can feed you thousands of rares per day. Jets have a short range, but this is not an issue if you are playing defense. They don't have far to fly. Bombers are coming to you. Patrol over their strike locations or patrol to intersect their patrols. Kill the enemy fighters first, and then focus on the bombers, if you can. It's possible to come back and win air superiority this way.
2. Give up on the air force completely. Research and build the best AA defense you can. Most players neglect AA guns completely, or walk around with a handful of level 1 guns as a show of force. That's not going to work against a determined air force. If the enemy is flying level 3 bombers, you should be building level 3-4 AA guns. This is not a sideshow, this requires serious investment. And in some cases it's a better option, especially if you already have high level ordnance plants but lack high level secret factories. Play to your strengths. Keep your AA in stacks of 5-10 and stack them with your armies. The opponent will not be able to hurt your units. Push the border out, beat the enemy on the ground, and their air force will not be able to stop you.
It's hard to play when the enemy has air superiority. But it is possible. Good luck!