Communication with AWS IoT Core

Hi!

I’m using LMIC in my ESP32 +RFM95 and I am using AU915-1 DR4 to transmit packages, ABP mode, Lorawan 1.0.3 and payload has 46 bytes. There are 24 devices registered on IotCore. Only 21 communicating. Each device sends confirmed uplink every 10 seconds. There are 16 devices communicating with Dragino LPS8 There are 8 devices communicating with Dragino DLOS8.

After packet 65536 I am having trouble with some devices that stopped to transmit, but in Gateway I can see this device transmitting.

Before I was using Chirpstack with Fcnt validator disabled and worked very well, but in IoT Core has not this option.

Can someone help me?

Thansk!