PC not going to sleep + slightly higher idle coolant temps

My coolant temperature at idle is now around 37–40°C, whereas it used to stay closer to 34°C before. Not sure if this small increase is normal or something to be concerned about.

Also, my PC is not going into sleep mode anymore. It just keeps running continuously, even when left idle for a long time.

I haven’t made any major hardware changes recently, so I’m unsure what’s causing this.