Here is what we do to kill the orphan sessions to make room.
List of Sessions
C:\Users\CyberArkDBA>qwinsta /server:parisdb02p
SESSIONNAME USERNAME ID STATE TYPE DEVICE
services 0 Disc
console 1 Conn
CyberArkDBA 9 Disc
31c5ce94259d4... 65536 Listen
rdp-tcp 65537 Listen
Reset a Session
Look for the ID that you want to reset. In this case, it is ID #9.C:\Users\CyberArkDBA>rwinsta 9 /server:parisdb02p /V
List of Sessions again
C:\Users\CyberArkDBA>qwinsta /server:parisdb02p
SESSIONNAME USERNAME ID STATE TYPE DEVICE
services 0 Disc
console 1 Conn
31c5ce94259d4... 65536 Listen
rdp-tcp 65537 Listen