When I unplug my Stylo 4 it beeps like it is charging over and over. When I plug it into the charger sometimes it says fast charging and sometimes I get a notification that says it is slow charging. It has a C style charger.
Welcome to Android Central! Check to make sure the port is clear of any debris -- use a can of compressed air to blow it out. Also use a Q-tip dipped in rubbing alcohol to clean the contacts.
Have you tried different cables? It could be a problem with your current cable's connection. If the same thing happens with other cables, then it's probably an issue with the port itself. Is the phone still under warranty?