about possibility to put incline for indoor treadmill runnings

Hello, at last winter came here on North of Russia, and now I have to stop running outside. Started to run indoor on treadmill till next May. My treadmill has minimal permanent incline 7.5 degrees. It is possible to make it higher but not less. So, I can easily run outside with speed 10-11 kmh but on treadmill I can run just with speed about 8-9kmh and even with this speed it is hard for me, i'm feeling that I spending more energy for such running but in Garmin Connect all my running statistic is going down. So, now it looks very stupid to run indoor without possibility to adjust incline. Maybe anybody knows how to turn on this adjusting in indoor run activity? And if it is not possible now maybe would be good for Garmin team to include this possibility???