Ambari nullpointer exception after loading previous HDFS config

[#1]

I made a change on my hdfs advanced config using the Ambari webui and then wanted to go back to a previous state using the saved configuration. After doing that, something broke. Ambari will not load the config menu anymore, I just get a spinning icon.

I checked the ambari-server log and this is what comes up:

Error Processing URI: /api/v1/clusters/clustername/configurations/service_config_versions - (java.lang.NullPointerException) null

I attempted performing a service restart for ambari-server on the name node but that didn't help the situation.

How can I manually revert the config version? 

I'm using Ambari 2.5.2 with HDP 2.6.2

[#2]

I tried reverting to a previous config using the api but something still broken with the retrieval of the service configuration version. Any suggestions on where to fix this on the master node??

28 Aug 2019 20:18:39,789 WARN [ambari-client-thread-763] ServletHandler:561 - Error Processing URI: /api/v1/clusters/***/configurations/service_config_versions - (java.lang.NullPointerException) null
28 Aug 2019 20:18:39,796 ERROR [ambari-client-thread-644] ReadHandler:102 - Caught a runtime exception executing a query
java.lang.NullPointerException

28 Aug 2019 20:18:39,797 ERROR [ambari-client-thread-644] ContainerResponse:419 - The RuntimeException could not be mapped to a response, re-throwing to the HTTP container
java.lang.NullPointerException
at org.apache.ambari.server.controller.ConfigurationResponse.<init>(ConfigurationResponse.java:94)
at org.apache.ambari.server.state.cluster.ClusterImpl.getServiceConfigVersionResponseWithConfig(ClusterImpl.java:2544)
at org.apache.ambari.server.state.cluster.ClusterImpl.getServiceConfigVersions(ClusterImpl.java:2472)