Yes, you can request a reimbursement for any qualified medical expenses paid with after-tax dollars, SO LONG AS the expenses were incurred after the start of your HSA (generally when you made the initial contribution).

This is true even if the reimbursement is years after the medical service you paid for, so long as the medical service in question occurred after your HSA was started.

[Edited 3/20/2020 2:43 pm CDT - typo]