The nest is blowing cool air on heating

[atfenway]

My nest always change from hot air to cool air before reaching at target temp.

When the heat is on, it starts well with hot air but suddenly changed to cool air even before being warm enough.

Nest keeps saying it is heating but cannot get to the level I want to be at since it is just cooling the house.

I didn't have this problem when I had old thermostats and even when I started to switch to Nests.

It just started to show this recently

Anyone had this issue? and kind to share how you dealt with it?

Many thanks

[Amartin8143]

I started have a similar issue. My heat is on 75 and everything is working well. Out of nowhere my house will get really cold even tho the heat is still on. I don’t have the energy save on but my house will drop to a curtain temperature then heat back up.

[Dr007]

mine does the same. There is no actual support for these devices they just let us complain to each other. Trash

[Sarha]

Mine suddenly started switching Heat and cool and Nest support basically just told me to buy a new one.