Netbackup Client Service is set for automatic but keeps ending

Nov 12, 2017 2:21:13 AM - Info bpbrm (pid=4656) connect failed STATUS (18) CONNECT_FAILED
Nov 12, 2017 2:21:13 AM - Info bpbrm (pid=4656)     status: FAILED, (43) CONNECT_RESET; system: (104) Connection reset by peer; FROM 0.0.0.0 TO {client} {IP} bpcd VIA pbx
Nov 12, 2017 2:21:13 AM - Info bpbrm (pid=4656)     status: FAILED, (42) CONNECT_REFUSED; system: (111) Connection refused; FROM 0.0.0.0 TO {client} {IP} bpcd VIA vnetd
Nov 12, 2017 2:21:13 AM - Info bpbrm (pid=4656)     status: FAILED, (42) CONNECT_REFUSED; system: (111) Connection refused; FROM 0.0.0.0 TO s{client} {IP} bpcd
Nov 12, 2017 2:21:13 AM - Error bpbrm (pid=4656) cannot connect to {client}, Operation now in progress (115)
Nov 12, 2017 2:21:13 AM - Info bpbkar (pid=0) done. status: 58: can't connect to client
Nov 12, 2017 2:21:13 AM - end writing
can't connect to client  (58)

The master is version 8.0; the client is 7.7.2.

The Netbackup Client Service is set for automatic but keeps ending. We restart the service and the backup completes. Why is the service keep stopping?