Hive & Apple Home - unsure which is glitching!

I have my Hive set to always on at 20.5 (house, new build, well insulated and so heating is ultimately rarely on) and one room at 21.5 (baby room). Apple home is also 20.5. Every so often the house feels hot, which is odd and I check and the Home app is saying it is heating to 25. I have never set it to 25!

Is this a glitch or something? Anyway of changing a setting, I think it seems like its an auto boost or something.

Any help appreciated!