First of all: welcome back. It's easy to start using Havenwise again if you used it in the past. Depending on whether you deleted your account or not, there are two different paths you need to take.
I didn't delete my Havenwise account
This is the easiest option. To get started:
Redownload the Havenwise app and log in with your old account. If you've forgotten your password, you can reset this in the app
Select heating and hot water optimisation and hit launch
Double check your schedules are still set how you'd like them to be
Double check your tariff is up to date
You're all done. You don't need to go through the learning mode again - Havenwise still knows how your home heats and cools and starts optimising again immediately
I deleted my Havenwise account
If you deleted your account less than 14 days ago, just log back in with your existing email and password. Your account will be reactivated, and you can follow the steps in the section above. If it's been more than 14 days, your account and data have been deleted, so you'll need to set up again:
Redownload the Havenwise app and create a new account.
Follow the steps in app to link your heat pump and set up your account
You will have to go through the learning mode again, as we deleted all your data along with your account. This will take around 2-3 days.
If you get stuck or there is something you can't remember, use one of the setup guides on the help centre or get in contact with support using the question mark button at the top right of the app.