The phrase "to follow up" means to take action or continue an activity after a period of inactivity, or to check on something that has already been done. Full definition
The sales reps are tasked each week with following up with three of their worst offending customers. (inc.com)
It feels a little like the classic abusive - husband approach, with punches followed up by flowers, in order to create a dependent relationship. (fortune.com)
I'm now far more interested in following up on recommendations from my new friend — and going to yoga class — than I am in writing papers. (sciencemag.org)