Daniel what is happening is as follows.
PowerBI data / dashboards can be worked in two different formats.
The first is DESKTOP
In it you work with the application installed on your PC
The second is the ONLINE
You manipulate the data here through the web, without needing any previous installation on your PC.
In your case you created your chart in DESKTOP, and linked some data from your SQL. After doing so you published the file, and at that time both your graph and your data (which are inside the powerBI file itself) went to the cloud, and became available for ONLINE access.
It happens that when you click on 'UPDATE' in the Desktop app it updates the file on your machine and not on the web. That is, to update both the graphic and the data you want will be necessary again 'PUBLISH' the file (replacing the previous one).
To not have to publish again every time you update something you can use an item called 'Data Gateway'
Follow a link explaining this:
Data Gateway