It happens
My Pre-Cal teacher failed me despite me going to tutors, having a roommate who was getting his master's in math tutoring me, going to the professor himself for tips and confirming he grades based on a curve, as well as not if you got the problem right but the steps and logic you used to arrive at your conclusion. I attended more classes than my friend who attended the same class, got tutoring every other week and was always following the latest course material. He gave me a failing grade by 5 points

I legitimately showed I wanted to get an understanding of the material and gave it more effort than I give my core major classes. There are a million and one different reasons he failed me by such a small amount beyond him being a fat ugly jealous racist CAC - But I put it behind me took it as a lesson that I need to humble myself and take remedial math in order to graduate and focus on my strengths at the time which were foreign language, history, marketing and poly sci.
Sometimes there is nothing you can do. For an accounting degree a B+ average in college it will be a little tougher upon graduating but as long as you focus on getting strong internships and networking you'll be fine. Worse comes to worst we need accounting majors in Digital Marketing and Ad Tech
Your GPA isn't everything. I'm 7 years out and yeah you have the occasional job description that says you should have graduated with this major and this GPA. As soon as they look at my resume they aren't caring about no damn GPA.

High GPA doesn't prepare you for the real world, teach you how to communicate with colleagues, speak CAC and other intangibles essential for surviving even basic corporate jobs. Recruiters know this so by the time you are in your 3rd year of your career you can safely laugh at GPA particularly if you have worked with big companies by then or picked up a highly needed skill.