Red Double Doors Won't Open in Office Complex

I’m in Office Complex, I’m at the part where you must dodge lasers to hit a green button to raise a forklift, then dive behind it to flip the switch to disable the lasers. Success! But then when I go up the stairs to open the red double doors, they don’t open. (Also, there is one Guard with me.) I checked a YouTube video and the doors opened for them. Did I miss a step somewhere?? Frustrating!

Founded in 2004, Leakfree.org became one of the first online communities dedicated to Valve’s Source engine development. It is more famously known for the formation of Black Mesa: Source under the 'Leakfree Modification Team' handle in September 2004.