forticlientsslvpn cli failing with "serial link appears to be disconnected"

Version: 4.4

Logs:

remote IP address 1.1.1.1 Script /etc/ppp/ip-up started (pid 23068) Script /etc/ppp/ip-up finished (pid 23068), status = 0x0 No response to 4 echo-requests Serial link appears to be disconnected. Connect time 2.5 minutes. Sent 17815 bytes, received 0 bytes. Script /etc/ppp/ip-down started (pid 23097) sent [LCP TermReq id=0x2 "Peer not responding"] Script /etc/ppp/ip-down finished (pid 23097), status = 0x0 sent [LCP TermReq id=0x3 "Peer not responding"] Connection terminated. Modem hangup

Please help! This seems to happen since earlier today.