If you have ArubaOS 8.x deployed with an MM, the power ranges in the 802.11a and 802.11g radio profile are used to control the power. If you do not have an MM, the power ranges in the ARM profile under the radio profile are used the control the power. Looking at the access points on the Dashboard should tell you the current transmit power.
Also how do you have the AP365 mounted? How high and at what angle? Your clients could be out of the coverage area of the access point. The aP365 can send a signal pretty far outdoors if the client is in the coverage area, even at lower power...