Scenario:

You have a working PowerApps connected Flow.

Everything working as expected.

Then you make a change in the flow by introducing new flow actions and voila – Template Error – see below:

The link provided in the error message talks about how to use functions in Logic Apps and Power Automate. It is not helpful.

The reason why we have this error is that the template that was bound to PowerApps didn’t include the new Action item(s) that we introduced hence they can’t be referenced.

The solution is to go to PowerApps and delete the Reference to the Flow (see below) then Add it back again.

That should fix the “template error”.

Something else to remember about PowerApps triggered flows:

It will always run in context of the User who triggered the flow in PowerApps.

We therefore have to make sure that all the PowerApps users will have access to the data sources referenced in Flow.