Hey Philip,
By our records, you are working with GoodData Platform and not with the GoodData Cloud product. Therefore, I'd suggest to use a different channel for your future enquires:
#gooddata-platform.
And speaking about your actual issue, best option would be to contact your Project Admin.
There are multiple reasons for missing dataset(s) or missing data in general. Changes within you data source or logical data model, some user permissions/restrictions being applied to your user,...