I am getting below error on MSFC since last few days
IP-4-DUPADDR: Duplicate address10.2.221.35 on Vlan23, sourced by 0000.0c07.ac0b
you probably have two MSFC in chassis1 and two MSFC in chassis2= 4 MSFC
Vl23 11 120 P Active local 10.2.221.34 10.2.221.35
Vl23 18 105 Active local 10.2.221.33 10.2.221.35
you are using two different HSRP groups 11 and 18 with the same virtual address 10.2.221.35 this is not correct!
Or you have the same HSRP group on all MSFCs or you associate a different vrtual address to group 18
Clearly first option making a single group including up to 4 MSFCs is the more useful choice.
the 4 MSFCs can have 4 different HSRP priorities for the same group
From your SVI configuration my guess is that you are using DRM the older method to handle MSFC redundancy
POY_MSFC2#sh running-config interface vlan 23
Current configuration : 362 bytes
description ***** PSF Segment 1 VLAN *****
ip address 10.2.221.32 255.255.255.0 alt ip address 10.2.221.34 255.255.255.0
ip helper-address 10.2.161.2
ip helper-address 10.2.161.17
no ip redirects
standby 11 priority 120 preempt alt standby 11 priority 115
standby 11 ip 10.2.221.35 alt standby 11 ip 10.2.221.35
hold-queue 125 in
so all 4 MSFCs are alive and connected to outside world
I would suggest to use the same standby group everywhere, only one device will be active, one MSFC will be standby and the other two will be in HSRP listen state.
with SRM you would have only two MSFCs on line and no need to use the alternate command
Hope to help