ML thinks that FL cheated on him

This can just be at some point during the story, but basically the FL starts becoming close to the SML while she's dating the ML, the SML tries something and the ML thinks she's cheating on him so she has to fix the misunderstanding. The SML tries to make it worse so she will come to him, but gets harshly rejected.

https://mydramalist.com/32725-how-boss-wants-to-marry-me

The second female lead organize a lot of traps for the FL and the SML which is the best friend of the ML to make the ML feel suspicious