MQTT get values from broker after Integration restart

Hi, i have a bridge between my HA MQTT broker (Official Addon) and another MQTT broker.
When i restart the MQTT Integration, all sensors show Unknown. But when i connect via MQTT-Explorer or other tools to my HAs MQTT broker, i can still see the topics i am interested in.

Is there a way to use tha data stored in the broker? I can not configure how the topics are published (“Smart” Camera)

The devices that send the messages need to send their messages with the retained flag set. That way home assistant will receive all retained topics when it reconnects.

Sadly I can not change the behavior of the Smart Camera.

Is there another workaround? I can see messages after connecting with MQTT Browser Even without the flag and if they are very old.

Not that I know of.