Can not add 1 ESX server

Can not add 1 ESX server

Good afternoon.
We have 4 ESX servers. At all the same credentials. 3 ESX servers added with no problems in the monitoring system (OpManager, Build 8811). After adding a fourth server I get a notice that it is successfully added, but not on the list.
Can you please tell how can I fix it?

                  New to ADSelfService Plus?