Dear all.
I have setting free Hot-sport for my rented house.

The issues is the signal. When people outside their room, they can use normally, but when they go inside, the signal down to 2/3 but cannot play anything on YouTube.
 

Any suggestion I can improve it. Or need more detail, let me know. Thanks

The room are ground floor 2.5meter height. Build with light weigh Lego brick 1dm deep. Roof are aluminum sheet. The EAP110-Outdoor install over the roof 1 meter.

The room that 5 meter away from EAP110-Outdoor can be use inside the room, but also not smooth. Farther then that it won't work. I expect 10-15 meter radius.