[admin@MikroTik] > ip route print
Flags: X - disabled, A - active, D - dynamic, C - connect, S - static, r - rip, b - bgp, o - ospf, m - mme, B - blackhole, U - unreachable, P - prohibit
# DST-ADDRESS PREF-SRC GATEWAY DISTANCE
0 ADS 0.0.0.0/0 lte1 2
1 ADC 100.88.104.152/32 100.88.104.152 lte1 0
2 ADC 192.168.88.0/24 192.168.88.1 bridge 0




[admin@MikroTik] > tool traceroute 8.8.8.8
# ADDRESS LOSS SENT LAST AVG BEST WORST STD-DEV STATUS
1 100% 1 timeout
2 100% 1 timeout
3 100% 1 timeout
4 100% 1 timeout
5 0% 1 0ms

[admin@MikroTik] > tool traceroute 8.8.8.8 src-address=100.88.104.152
# ADDRESS LOSS SENT LAST AVG BEST WORST STD-DEV STATUS
1 100% 2 timeout
2 100% 1 timeout
3 100% 1 timeout
4 100% 1 timeout
5 100% 1 timeout


[admin@MikroTik] > /export
# jan/02/1970 00:18:55 by RouterOS 6.47
# software id = 1UEX-MQEN
#
# model = RBSXTR
# serial number = C6190B15F97C
/interface lte
set [ find ] mtu=1480 name=lte1 pin=0000
/interface bridge
add admin-mac=C4:AD:34:80:A8:23 auto-mac=no comment=defconf name=bridge
/interface list
add comment=defconf name=WAN
add comment=defconf name=LAN
/interface wireless security-profiles
set [ find default=yes ] supplicant-identity=MikroTik
/ip hotspot profile
set [ find default=yes ] html-directory=flash/hotspot
/ip pool
add name=dhcp ranges=192.168.88.10-192.168.88.254
/ip dhcp-server
add address-pool=dhcp disabled=no interface=bridge name=defconf
/user group
set full policy=local,telnet,ssh,ftp,reboot,read,write,policy,test,winbox,password,web,sniff,sensitive,api,romon,dude,tikapp
/interface bridge port
add bridge=bridge comment=defconf interface=ether1
add bridge=bridge comment=defconf interface=ether2
/interface list member
add comment=defconf interface=bridge list=LAN
add comment=defconf interface=lte1 list=WAN
/ip address
add address=192.168.88.1/24 comment=defconf interface=ether1 network=192.168.88.0
/ip dhcp-server network
add address=192.168.88.0/24 comment=defconf gateway=192.168.88.1
/ip dns
set allow-remote-requests=yes
/ip dns static
add address=192.168.88.1 name=router.lan type=A
/ip firewall filter
add action=accept chain=forward comment="defconf: accept in ipsec policy" ipsec-policy=in,ipsec
add action=accept chain=forward comment="defconf: accept out ipsec policy" ipsec-policy=out,ipsec
add action=fasttrack-connection chain=forward comment="defconf: fasttrack" connection-state=established,related
add action=accept chain=forward comment="defconf: accept established,related, untracked" connection-state=established,related,untracked
add action=drop chain=forward comment="defconf: drop invalid" connection-state=invalid disabled=yes
add action=drop chain=forward comment="defconf: drop all from WAN not DSTNATed" connection-nat-state=!dstnat connection-state=new disabled=yes in-interface-list=WAN src-address=0.0.0.0
/ip firewall nat
add action=masquerade chain=srcnat comment="defconf: masquerade" ipsec-policy=out,none log=yes out-interface-list=WAN

Maybe you not pay bill and they give you a connection without internet .

Maybe you not have a proper DNS at ROS or end pc ?

Maybe other APN ?

What lte module you have ?

The problem is when i trying to set passthrough mode on my SXT LTE i got RouterOS WinBox Error: "Couldn't change LTE APN <name> - Passthrough not supported for this device! (6) - six it's (i think) error code.