We developed a flow and added it on page layout with hep of quick action, though button was visible, but clicking on it was producing error.
We changed the approach, I added that screen flow directly on Record page by editing Lightning experience builder, but the problem still persisted.
HOW DID WE FIX IT?
We provided permission “Run Flows” on user’s profile and it worked! More detail about this permission is below:
Run Flows – Allows the user to run flows in Salesforce. So in your case the user didn’t have permission permission to run the flow explicitly. This permission must be given to successfully run the flows by the user.
Check this doc for more information: https://help.salesforce.com/articleView?id=vpm_admin_flow_detail.htm&language=nl&type=0
For more information on the permission controlled by profile, check this out: https://help.salesforce.com/articleView?id=000198725&type=1