How to downgrade RAK7240 to 1.3.2 from WisDM?

Issue: Since upgraded to 1.3.5 and 1.3.6, device RSSI are always 0 when I supposed to be between -55 and -96

Setup: WisDOM Cloud registed RAK7240

LoRa® Server: Packet forwarder - Semtech UDP GWMP Protocol - Chirpstack

I want to downgrade back to 1.3.2 a Gateway RAK7240. It’s possible to done from WisDM ?