Unable to start cmk-agent-ctl while installing

sudo apt install ./check-mk-agent_2.1.0p28-1_all.deb
Reading package lists… Done
Building dependency tree… Done
Reading state information… Done
Note, selecting ‘check-mk-agent’ instead of ‘./check-mk-agent_2.1.0p28-1_all.deb’
The following NEW packages will be installed:
0 upgraded, 1 newly installed, 0 to remove and 39 not upgraded.
Need to get 0 B/4030 kB of archives.
After this operation, 4159 kB of additional disk space will be used.
Get:1 /home/ubuntu/check-mk-agent_2.1.0p28-1_all.deb check-mk-agent all 2.1.0p28-1 [4030 kB]
Selecting previously unselected package check-mk-agent.
(Reading database … 111368 files and directories currently installed.)
Preparing to unpack …/check-mk-agent_2.1.0p28-1_all.deb …
Unpacking check-mk-agent (2.1.0p28-1) …
Setting up check-mk-agent (2.1.0p28-1) …

Deploying agent controller: /usr/bin/cmk-agent-ctl
…Not running on this system. Falling back to legacy systemd setup.
Deploying systemd units: check-mk-agent-async.service check-mk-agent.socket.fallback check-mk-agent@.service
Deployed systemd
Deactivating systemd unit ‘cmk-agent-ctl-daemon.service’ (if active)…
Activating systemd unit ‘check-mk-agent-async.service’…
Created symlink /etc/systemd/system/multi-user.target.wants/check-mk-agent-async.service → /lib/systemd/system/check-mk-agent-async.service.
Activating systemd unit ‘check-mk-agent.socket’…
Created symlink /etc/systemd/system/sockets.target.wants/check-mk-agent.socket → /lib/systemd/system/check-mk-agent.socket.
Scanning processes…
Scanning candidates…
Scanning linux images…

Restarting services…
Service restarts being deferred:
systemctl restart networkd-dispatcher.service
systemctl restart systemd-logind.service
systemctl restart unattended-upgrades.service

No containers need to be restarted.

No user sessions are running outdated binaries.

No VM guests are running outdated hypervisor (qemu) binaries on this host.
N: Download is performed unsandboxed as root as file ‘/home/ubuntu/check-mk-agent_2.1.0p28-1_all.deb’ couldn’t be accessed by user ‘_apt’. - pkgAcquire::Run (13: Permission denied)

unable to start cmk-agent-ctl on my ubuntu system . How to resolve it ?

check_mk_agent is running fine .
systemd is using the 6556 port
cmk-agent-ctl is not being started.