Thanks for the feedback, and you didn’t do anything wrong: it’s a bug on our end.
The price not following your contract
The widget is linked to a specific contract. When the rate changes, a new contract is created (which is what you did on August 1st), but the widget remains on the old one. It then continues to display the old prices, without any warning. The scenes „Electricity price changes“ and „Current electricity price“ have the same problem.
I opened an issue: Energy price widget and energy price scenes keep using an expired contract after a tariff change · Issue #3353 · GladysAssistant/Gladys · GitHub
With the fix, the widget and the scenes will automatically follow the active contract of your meter: nothing to reconfigure at the next rate change, and the widgets already in place will continue to work.
In the meantime, you need to properly select the active contract in the widget, as you did. If you have scenes that use the electricity price, make sure to choose the active contract there as well.
„Blue off-peak“ instead of a real name
The rate labels are currently generated in English. I created a feature request to display them in your language („Blue HC“): Libellés des tarifs dans la langue de l’utilisateur (« Bleu HC » plutôt que « blue off-peak »)
Don’t hesitate to vote for it. It also explains how to manually rename the labels in the meantime.
A small question
On your screenshot, the widget announces „0.1325 €/kWh (off-peak)“ starting at 06:00, whereas at 06:00 we switch to full hours. I suspect that the Tempo color of the next day was not yet known to Gladys.