LoRaWAN confirmed data up, backoff before retry?


I’m using the LoRaWAN stack from Mbed OS. The uplink messages transmitted are CONFIRMED. When the acknoledge is not received, the message is retransmitted up to 3 times.

The problem is that the retries are transmitted direct after the previous one without any backoff and if something else is doing e.g a join request during this time, there is sometimes a collision for all the retries. Is there a possibility to add a backoff between the retries to prevent this problem?