Connect script failed

[liuguohuan-xiezuo]

这是执行脚本的日志，模块是EC20，执行脚本的时候有时候能成功拨号，太部分时候是失败，但只要拨号成功一次，后面再次拨号也会成功
./quectel-pppd.sh
quectel-pppd options in effect:
devname /dev/ttyUSB3 # (default)
apn ctnet # (default)
user user # (default)
password passwd # (default)
root@firefly:/etc/ppp/peers# pppd options in effect:
debug # (from command line)
nodetach # (from command line)
dump # (from command line)
noauth # (from command line)
user user # (from command line)
password ?????? # (from command line)
/dev/ttyUSB3 # (from command line)
115200 # (from command line)
lock # (from command line)
connect ''chat -s -v ABORT BUSY ABORT "NO CARRIER" ABORT "NO DIALTONE" ABORT ERROR ABORT "NO ANSWER" TIMEOUT 30 "" AT OK ATE0 OK ATI\;+CSUB\;+CSQ\;+CPIN?\;+COPS?\;+CGREG?\;\&D2 OK AT+CGDCONT=1,\"IP\",\"ctnet\",,0,0 OK ATD#777 CONNEC
# (from command line)
disconnect chat -s -v ABORT ERROR ABORT "NO DIALTONE" SAY "\nSending break to the modem\n" "" +++ "" +++ "" +++ SAY "\nGood bay\n" # (from command line)
nocrtscts # (from command line)
modem # (from command line)
asyncmap 0 # (from /etc/ppp/options)
lcp-echo-failure 4 # (from /etc/ppp/options)
lcp-echo-interval 30 # (from /etc/ppp/options)
hide-password # (from /etc/ppp/options)
novj # (from command line)
novjccomp # (from command line)
ipcp-accept-local # (from command line)
ipcp-accept-remote # (from command line)
noipdefault # (from command line)
ipcp-max-configure 30 # (from command line)
defaultroute # (from command line)
usepeerdns # (from command line)
noccp # (from command line)
noipx # (from /etc/ppp/options)
abort on (BUSY)
abort on (NO CARRIER)
abort on (NO DIALTONE)
abort on (ERROR)
abort on (NO ANSWER)
timeout set to 30 seconds
send (AT^M)
expect (OK)
^M
alarm
Failed
Script ''chat -s -v ABORT BUSY ABORT "NO CARRIER" ABORT "NO DIALTONE" ABORT ERROR ABORT "NO ANSWER" TIMEOUT 30 "" AT OK ATE0 OK ATI;+CSUB;+CSQ;+CPIN?;+COPS?;+CGREG?;&D2 OK AT+CGDCONT=1,"IP","ctnet",,0,0 OK ATD#777 CONNECT'' finished (pid 4869), status = 0x3
Connect script failed