Rsyslog client and SCHANNEL based server unable to decrypt the message when extended buffer contains additional data

Question

At present we are using the rsyslog on Linux machine to send the message using TLS 1.2 which internally use GnuTLS library send the syslog message to one of our hosted server which accept the TLS data using the windows SCHANNEL method. We are getting the "Couldn't Decrypt, error code:80090308" some case when the client sends more than 16K data to the server. On saving the data on the extended buffer also noticing the same problem during the next cycle data decryption.