You may not turn off permission Can use dashboards without same license type as running user for this License Type
I managed to get round this by using a permission sets until SF fix this issue as I don't fancy updating all the dashboards.running user
This is Michelle from Salesforce.
I've taken ownership of case 21255940 which is about an error message you're receiving when enabling permission to Profiles.
Upon further review, this issue has already been tagged and raised to our Research & Development team for further investigation. For now, what we can do is to escalate the case to our higher tier of support so that we can track the updates from R&D and note that your organization is also affected by this concern.
"The error message pertains to permission given in platform users in relation to the Dashboards. For this case, it is advisable to make sure that the dashboards being shared to users under this profile have the same license type with the running user of the dashboards. "
"This is an ongoing issue that is affecting multiple customers. Our Product team is aware of the issue and are working as quick as possible to resolve the issue. They plan on implementing a fix by the end of this week (Safe Harbor)."