D400 ug misfiring

Hi guys, wanted to just check on the issue which I am facing on my Dominar 400. So whenever I start my bike on idle, it runs really fine, but as soon as I open up a little bit of throttle, my bike starts to misfire a lot. My Mechanic said that it could be an issue with the fuel pump. For now. I have just replaced the fuel filter, which resolve the issue for like a week, and now I am again started getting the same issue.

Please let me know if anyone has a solution which all things to check for this issue and what could be the main reason is it the fuel pump or something else also needs attention