Does this only happen in your office? Does the office have 'decorator plants'? Does a service 'do' the plants, or a well-meaning person in the office. Go around and check the plant's water trays, and if one is always soggy [stick your finger on top of the dirt and if you get dirt particles on your finger 3 times -Mon, Wed, Fri] I will be you'll find gnats or fruit-fly like critters living in the dirt...and the plant won't look to healthy. Plant is overwatered, roots are rotting and bugs are attracted - until a more tasty morsel comes along, such as you! Move the plant, and water it less and Maybe, that will help. I have been the company plant doctor in prior lifes...and rarely ever had to use pesticides...just good care.
Well, It may seem far-fetched, but, I have known it to happen!
Worth a try I guess!
May we soon hear you are bug-free! - j