arduino PubSubClient retain flag is always set

[Hans-Zwiesel]

I use PubSubClient version=2.8 with Arduino on esp8266

When I publish mqttClient.publish(Subs59, RoDa_Kd_mode.c_str(),false);

the retain Flag is always set (Iobroker admin objekts )

I already send "mqttClient.publish(Subs59, "",true);" to clear the retain flag in the broker and
restart the mqtt instance.

Who can help?
regards
Hans