Cannot call to my PBX through my PSTN line

Hi all
I got install AX-400P atcom card with 2 FXO and 2 FXS moduls. My problem is that after period of time I cannot call in to my PBX through my PSTN lines? both of them doesnt respond. When I try to call I got error like the line is not connect.

DEBUG[22474] app_db.c: Ignoring, no parameters
VERBOSE[22474] logger.c: – Executing [t@ivr-5:2] Set(“Zap/2-1”, “__NODEST=”) in new stack
VERBOSE[22474] logger.c: – Executing [t@ivr-5:3] Goto(“Zap/2-1”, “ivr-5|s|begin”) in new stack
VERBOSE[22474] logger.c: – Goto (ivr-5,s,9)
VERBOSE[22474] logger.c: – Executing [s@ivr-5:9] Set(“Zap/2-1”, “TIMEOUT(digit)=3”) in new stack
VERBOSE[22474] logger.c: – Digit timeout set to 3
VERBOSE[22474] logger.c: – Executing [s@ivr-5:10] Set(“Zap/2-1”, “TIMEOUT(response)=3”) in new stack
VERBOSE[22474] logger.c: – Response timeout set to 3
VERBOSE[22474] logger.c: – Executing [s@ivr-5:11] Set(“Zap/2-1”, “__IVR_RETVM=”) in new stack
VERBOSE[22474] logger.c: – Executing [s@ivr-5:12] ExecIf(“Zap/2-1”, “1|Background|custom/ZapowiedzNumerVin”) in new stack
VERBOSE[22474] logger.c: – <Zap/2-1> Playing ‘custom/ZapowiedzNumerVin’ (language ‘pl’)
VERBOSE[22474] logger.c: – Executing [s@ivr-5:13] WaitExten(“Zap/2-1”, “|”) in new stack
VERBOSE[22474] logger.c: – Timeout on Zap/2-1, going to 't’
VERBOSE[22474] logger.c: – Executing [t@ivr-5:1] DBdel(“Zap/2-1”, “”) in new stack

I am using a Digium TDM 410P card port 1 and port 4 . In port4 I have put a pstn line but I am unable to make and receive calls from outside. I have added a ZAP trunk in which I am using channel 4 instead of g0 which now looks like ZAP4. and I have added ZAP4 to inbound call and outbound call when I call out from my free pbx it says all circuits are busy or the person you are calling is unavailable. I am totally stuck from a week on it. Help appreciated please as I am very new to free pbx. My dahdi-channels.conf looks like this:

root@localhost asterisk]# vi dahdi-channels.conf
;;; line="1 WCTDM/0/0"
signalling=fxo_ls
callerid=“Channel 1” <4001>
mailbox=4001
group=5
context=from-internal
channel => 1
callerid=
mailbox=
group=
context=default

;;; line="4 WCTDM/0/3"
signalling=fxs_ks
callerid=asreceived
group=0
context=from-pstn
channel => 4
callerid=
group=
context=default

[root@localhost asterisk]# dahdi_cfg -vvv
DAHDI Tools Version - 2.1.0.2

DAHDI Version: 2.1.0.4
Echo Canceller(s): MG2
Configuration

Channel map:

Channel 01: FXO Loopstart (Default) (Echo Canceler: mg2) (Slaves: 01)
Channel 04: FXS Kewlstart (Default) (Echo Canceler: mg2) (Slaves: 04)

2 channels to configure.

Setting echocan for channel 1 to mg2
Setting echocan for channel 4 to mg2