Too many Deauthenticated Reason 2 messages - Debian Jessie - WiFi

I have a embedded device ruing Debian Jessie Keel 3.14.60 and have 2 WiFi chips on it:

• wlan0 - Intel 5100 with iwlwifi-5000 driver
• wlan1 - RealTek 8812au

When both the WiFi's are coected to an AP, I am seeing a lot of `wlan0: deauthenticated from 50:17:ff:XX:XX:XX (Reason: 2)` messages. This happens on both the interfaces periodically (every 30mins). When this happens, the device often loses its network coection.

Is there anything I can do so that this doesn't happen?