Not working for more than 2 people in the room without nat

hi all
when two people commect no problem to room when add one user add to room make problem for room
i do not use NAT… install on public server … how to resolve this porblem?
2020-04-18 18:06:36.837 INFO: [484] [confId=2cceb1f1d8c6318e gid=ff756a stats_id=Aubree-x2G conf_name=home ufrag=8jetr1e67l8gau epId=cc22554d local_ufrag=8jetr1e67l8gau] ConnectivityCheckClient$PaceMaker.run#919: Pair failed: 194.5.178.64:10000/udp/host -> 10.1.0.252:63774/udp/host (stream-cc22554d.RTP)

Are you on AWS?

No i user another data center that they do not use firewall for vps

How can help me?