BioOntology fields will not work in: SMS or IVR scenarios, the Mobile App (offline), most Action Tag setups.
The field setting connects you to a database managed by Standford University. If the field lookup functionality seems non-responsive or unavailable, the service may be temporarily down. Try again at a slightly later time and if still not responding, contact an Administrator.
If your project uses a large amount of BioOntology fields (20+), you may experience slower responsiveness from REDCap.