LXD configure profile for static ip assignment

LXD
1

Hi, i use a profile for my containers, and the profile has an lxd managed bridge, now how would i enable the profile so that containers can get static ips.
the use case for using the parameter nat with proxy for some containers.

2 
lxc stop c1
lxc config device override c1 eth0 ipv4.address=10.96.212.100
lxc start c1
3

after doing the mentioned commands,

Error: Proxy connect IP cannot be used with any NIC static IPs
Try `lxc info --show-log c1` for more info

lxc info --show-log c1
Name: c1
Location: none
Remote: unix://
Architecture: x86_64
Created: 2020/03/07 08:55 UTC
Status: Stopped
Type: container
Profiles: default

Log:

lxc c1 20200307125325.284 ERROR    start - start.c:proc_pidfd_open:1644 - Function not implemented - Failed to send signal through pidfd
lxc c1 20200307125325.296 WARN     cgfsng - cgroups/cgfsng.c:chowmod:1525 - No such file or directory - Failed to chown(/sys/fs/cgroup/unified//lxc.payload/c1/cgroup.threads, 500000001, 0)

EDITE:
The problem was me mistakenly switching list and connect for proxy.