Ah, so now you provide a bit more crucial information.
So what you're really asking is "how does a USF player handle two players where one spams bunkers and the other covers the position with mortars?"
Get your teammates to help.
You could also use something like a jeep to drive past those bunkers. Soviet clown cars and satchels also help, but since this appears to be a question for USF in a 2v1 situation, I'd say get out of the balance forums and use the state office.
I am talking about general team games. If anyone denies Axis is click to win (As long as it is not against full Soviet team) is just being a fanboy. The maps in this game are designed for comptomping as they offer no flanking chance in 3v3 and 4v4 and unlike COH1 here one MG burst completely pins down the entire units within its radius regardless if the MG is shooting at them or not. Then you bring smoke and get pass the bunker to attack it from behind but you face another bunker which is covering the back of the first bunker. I faced this against both US and Axis bunker spamming players. There is no difference if it is US being covered by soviet mortars and spamming fighting positions or it is Axis spamming bunker and being covered by mortars or infantry guns.
These things are issue and it shows the bad design of the game. Such strategies should punish the player badly for making such stupid moves but sadly mostly because of the map design and game design it is very rewarding.