Beginner is trying to add a FC block to existing project and receives "Changed blocks open-must be saved now" message and it is evidently not loading to PLC and the FC never scans.

Question

I created a simple, single-in single-out network in a new FC, declared the variables, and saved it. I then added a new network in OB1 calling the new FC, filling in parameters as required. Everything was saved and I individually loaded all blocks to PLC, receiving the "Changed blocks" message each time. The PLC goes to run mode and original FC's 1 and 2 scan and interact with Factory IO simulator just fine. Attempting to monitor OB1 to ensure FC3 is being scanned yields a message telling me to save OB1. I have, as well as loading to PLC. No change. I am hoping for operator error, somewhere.