Taken over tenancy, linked with nest. Hot water stopped working.

[Frearson]

I recently moved into a house and hot water was fine. Now i reset the nest to connect to my app and i seem to have stopped the hot water. 
there is no option for water heating now which i have had on previous nests. 
please advise

[Frustratedddd]

Are you in the UK, do you have a system boiler? Have you searched this forum for the answer?