For the sake of just breaking a bench plateau there's lots of different things that can make the difference.
Changing rep schemes can help a lot, after 3-4 weeks the body may become accustomed to the stimuli and doesn't change much.
There's tons of different things people say will help you break a bench plateau, although I generally don't bench and I can't vouch for it to much although I can vouch for the theory and idea behind it.
No particular order;
Fix/Perfect your form, as simplistic as the bench is, you can make it technical and precise and different adjustments will add weight.
Board presses, floor presses
High rep dumbell bench or high rep pushups
Just take a break of benching for longer than a deloading work and do other exercises that will help your upper body pushing strength.
How much rowing are you doing; if it's not enough your body will try and prevent imbalances from going to extreme although it can definitely still get awful.
Variation is key, change up the bars, the reps, the speed, dumbbells, ROM, and others.
There's a reason kids that bench as heavy as they can go every time they go to the gym never make any progress. Your body will quit adjusting to the stimuli after time.
Just a few thoughts of mine.