Wifi always disconnect and never reconnect ( tablet android logicom )

Hi, i put my xiaomi routeur wifi 3G with lede a few weeks ago, everything works fine except one android tablet.
It always disconnect when idle and never reconnect automatically, i must choose the wifi ssid to connect.
Anybody have a idea?
wifi conf :

	Generic MAC80211 802.11bgn (radio0)
Channel: 11 (2.462 GHz) | Bitrate: 58.2 Mbit/s
 85%	SSID: ***| Mode: Master
BSSID: 34:CE:00:65:**** | Encryption: WPA2 PSK (CCMP)

	Generic MAC80211 802.11nac (radio1)
Channel: 36 (5.180 GHz) | Bitrate: ? Mbit/s	 Scan  Add
 0%	SSID: ***_5G | Mode: Master
BSSID: 34:CE:00:65:*** | Encryption: WPA2 PSK (CCMP)
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