Error:
Dec  7 10:47:55 DEBUG[3956] app_macro.c: Executed application: GotoIf
Dec  7 10:47:55 VERBOSE[3956] logger.c:     -- Executing Dial("SIP/402-09bb7f48", "ZAP/g0/0641299999|300|") in new stack
Dec  7 10:47:55 NOTICE[3956] app_dial.c: Unable to create channel of type 'ZAP' (cause 34 - Circuit/channel congestion)
Dec  7 10:47:55 VERBOSE[3956] logger.c:   == Everyone is busy/congested at this time (1:0/1/0)
Dec  7 10:47:55 DEBUG[3956] app_dial.c: Exiting with DIALSTATUS=CONGESTION.

asterisk1*CLI> pri show span 1
Primary D-channel: 3
Status: Provisioned, Up, Active
Switchtype: EuroISDN
Type: CPE (PtMP)
Window Length: 0/7
Sentrej: 0
SolicitFbit: 0
Retrans: 0
Busy: 0
Overlap Dial: 0
T200 Timer: 1000
T203 Timer: 10000
T305 Timer: 30000
T308 Timer: 4000
T313 Timer: 4000
N200 Counter: 3

/etc/asterisk/zapata.conf:
[channels]

switchtype = euroisdn

; p2mp TE mode (for connecting ISDN lines in point-to-multipoint mode)
signalling = bri_cpe_ptmp

pridialplan = unknown
prilocaldialplan = unknown
nationalprefix = 0
internationalprefix = 00
usecallingpres=yes

#include zapata_additional.conf

echocancel = yes
echocancelwhenbridged = yes
echotraining = 100

context="from-zaptel"
group = 1

; S/T port 1-4
channel => 1-2
;channel => 4-5
;channel => 7-8
;channel => 10-11

/etc/zaptel.conf:
# Autogenerated by /usr/sbin/genzaptelconf -- do not hand edit
# Zaptel Configuration File
#
# This file is parsed by the Zaptel Configurator, ztcfg
#

# It must be in the module loading order


# Span 1: ztqoz/1/1 "quadBRI PCI ISDN Card 1 Span 1 [TE] (cardID 0) Layer 1 DEACTIVATED (F4)" AMI/CCS
span=1,1,1,ccs,ami
# termtype: te
bchan=1-2
dchan=3

# Span 2: ztqoz/1/2 "quadBRI PCI ISDN Card 1 Span 2 [TE] (cardID 0) Layer 1 DEACTIVATED (F4)" AMI/CCS
span=2,1,1,ccs,ami
# termtype: te
bchan=4-5
dchan=6

# Span 3: ztqoz/1/3 "quadBRI PCI ISDN Card 1 Span 3 [TE] (cardID 0) Layer 1 DEACTIVATED (F4)" AMI/CCS
span=3,1,1,ccs,ami
# termtype: te
bchan=7-8
dchan=9

# Span 4: ztqoz/1/4 "quadBRI PCI ISDN Card 1 Span 4 [TE] (cardID 0) Layer 1 DEACTIVATED (F4)" AMI/CCS
span=4,1,1,ccs,ami
# termtype: te
bchan=10-11
dchan=12

# Global data

loadzone        = nl
defaultzone     = nl