Hey Everyone, I got the problem solved. I restored a previous version via Dropbox (where I keep all my files) and when opening the file, I chose "Open & Repair" as an option. The file must have gotten corrupted somehow and was acting up via the Story Settings Dialog box.
ArchiCAD 26 - iMac 27, Late 2019, 3.7 GHz Intel Core i5, 32GB Ram, Radeon Pro 8GB, macOS Sonoma