I thought there was a cap on out-of-pocket costs but my prescription drug benefit requires me to pay co-pays even after I’ve met the out-of-pocket limit for other medical benefits. Is that allowed?

Your employer plans can have a separate limit for your prescription drug coverage, but the total of all out-of-pocket caps combined cannot be more than $7,900 for an individual or $15,800 for a family in 2019. (HHS, Notice of Benefit and Payment Parameters for 2019, April 17, 2018).