Configure TLS for PingIdentity hosted in Kubernetes cluster

We are trying to send logs from an application hosted in kubernetes cluster to logstash via fluentd.
The logs are sent in syslog over TCP on an encrypted channel with TLS configuration. At the logstash end we are receiving the following error.

We have imported the TLS certificates onto the application hosted in Kubernetes cluster.

[ERROR][logstash.inputs.tcp ][main][2e881b33b1ae0b84fc8ec28ef74ddbcb1874fc6a6f7db7466914f728f0ac94bb] null: closing due:
io.netty.handler.codec.DecoderException: io.netty.handler.ssl.NotSslRecordException: not an SSL/TLS record:

How can I ensure that the TLS certificate is properly imported. Please advise.

Thanks in advance.