could be a couple things, first things i would check:
1. Does the user your testing with have the proper access rights?
2. Save button emediatly triggers this microflow or is there a microflow before this? Could be youre passing on the DB object you used in a previous microflow for validation purposes (that way recommitting the old object as a first action this microflow (so check your object id's)
on another note, i dont know what else youre going to do with the providertype, and the providertype hanging behind the provider, but if youre only using the ID, you can use refID's from the other object and you dont need a seperate retrieve.