Networking is broken

[Saint Michael]

The LXC network is broken, and this may be a problem with the Kernel more than with LXC.
5.15.53-1-pve
I have some containers that cannot be pinged from either the host or another host on the same LAN (same subnet), but can talk to the outer world fine.
They can also talk to a host on the same physical network that has an IP address from a different Class C network.
when I ping them, I can see with tcpdump the pings coming and going:
17:19:19.478299 IP XX.95.11.6 > XX.95.11.202: ICMP echo request, id 13089, seq 1216, length 64
17:19:19.478330 IP XX.95.11.202 > 3XX.95.11.6: ICMP echo reply, id 13089, seq 1216, length 64
17:19:20.502263 IP XX.95.11.6 > XX.95.11.202: ICMP echo request, id 13089, seq 1217, length 64
17:19:20.502288 IP XX.95.11.202 > XX.95.11.6: ICMP echo reply, id 13089, seq 1217, length 64
17:19:21.526234 IP XX.95.11.6 > 3XX.95.11.202: ICMP echo request, id 13089, seq 1218, length 64
17:19:21.526264 IP XX.95.11.202 > XX.95.11.6: ICMP echo reply, id 13089, seq 1218, length 64

In this case the container being pinged is XX.95.11.202, and the pinger is XX.95.11.6

if I use tcdump on the pinger, I see the packets leaving but no response arrives.
The network on both containers is similar, but the pinger can also be a physical host on the same LAN.

I tried with every combination of networking possible
lxc.net.0.type=macvlan
lxc.net.0.macvlan.mode = bridge
lxc.net.0.hwaddr = ca:26:e9:28:30:23
lxc.net.0.flags = up
lxc.net.0.link = eno49
lxc.net.0.name = eth0
lxc.net.0.l2proxy=1 (also tried 0)
or
lxc.net.0.type = ipvlan
lxc.net.0.ipvlan.mode =l2
lxc.net.0.flags = up
lxc.net.0.link = eno50
lxc.net.0.name = eth0

even creating a bridge and using veth
how do I fix this? My entire business is based on intercommunicating containers.
netstat -i
Kernel Interface table
Iface      MTU    RX-OK RX-ERR RX-DRP RX-OVR    TX-OK TX-ERR TX-DRP TX-OVR Flg
eno49     1500 14302849506  84611   1475 84611  13811614424      0      0      0 BMRU
eno50     1500 487169602      0   1151 0        942329      0      0      0 BMRU
eth1      1500  1155437      0      0 0            16      0      0      0 BMRU
eth2      1500  1154864      0      0 0            15      0      0      0 BMRU
lo       65536   908263      0      0 0        908263      0      0      0 LRU

Philip