@starleaf1
What device was connected to this HS100 smart plug? Please verify whether it is a supported type by the smart plug, as the smart plug may get damaged if it is used to control an unsupported appliance for a long period.
Unplug the appliance and disconnect HS100 from the power outlet. Leave it unplugged for some time like 20-30mins. Monitor whether the problem still exists after powering it back on.
Try to factory reset the smart plug. How to factory reset the Kasa smart plug
The device might be defective if the above suggestions do not help. If the plug gets defective under normal use (e.g. NOT controlling an un-supported device), contact the retailer or local TP-Link support to proceed with the warranty.