Tested
Nat tables
;;; Ports redirect
chain=dstnat action=dst-nat to-addresses=192.168.1.2 to-ports=1723
protocol=tcp src-address-type="" dst-port=1723 log=yes log-prefix=""

[root@MikroTik] /interface bridge port> print
Flags: X - disabled, I - inactive, D - dynamic, H - hw-off
# INTERFACE BRIDGE HW PVID PR PATH-COS
0 Via Daddy bridge1 yes 1 0x 1
1 Via living ... bridge1 yes 1 0x 1
2 Ether5-Lan bridge1 yes 1 0x 1
3 bonding1 bridge1 yes 1 0x 1


[root@MikroTik] /interface bridge> ports
bad command name ports (line 1 column 1)
[root@MikroTik] /interface bridge> port
[root@MikroTik] /interface bridge port> print
Flags: X - disabled, I - inactive, D - dynamic, H - hw-off
# INTERFACE BRIDGE HW PVID PR PATH-COS
0 Via Daddy bridge1 yes 1 0x 1
1 Via living ... bridge1 yes 1 0x 1
2 Ether5-Lan bridge1 yes 1 0x 1
3 bonding1 bridge1 yes 1 0x 1

[root@MikroTik] /interface bonding> pr
Flags: X - disabled, R - running
0 R name="bonding1" mtu=1500 mac-address=00:37:27:E0:10:65 arp=enabled
arp-timeout=auto slaves=Via study room1,Via study room2 mode=802.3ad
primary=none link-monitoring=mii arp-interval=100ms arp-ip-targets=""
mii-interval=100ms down-delay=0ms up-delay=0ms lacp-rate=30secs
transmit-hash-policy=layer-3-and-4 min-links=0

You give no description re symptoms why it is not working!!!
It seems you are making ssinf some attributes in your port forwarding rule, name destination address and or in interface / list

I made a mistake, why can not dst 1723 port to other IP, bcoz when you want to port map 1723 port, you must enable pptp port in firewall-service ports and leave this parameter blank.
Please remove this topic.