Part 107 UAS pilot reported they inadvertently flew in restricted airspace without authorization. When the UAS app indicated they were in the airspace the pilot exited immediately and landed the UAS.

Narrative

What: Possibly entered Restricted Airspace.Where: County Jail -Sheriff DepartmentHow: Adequate depiction of airspace not shown on aeronautical chart/mapsFlight Summary:I was flying with verbal permission from the County Office to take pre-construction site photos. I had checked airspace using both SkyVector on my phone and Air Control (Aloft) also via my phone. Both showed no indication of the restricted airspace. Once I had taken off; the drones app notified me of a restricted airspace nearby. I promptly brought the drone back in to check via the drones app and saw that the jail was indicated as the footprint of the sheriffs office. I then continued the operation with the knowledge to stay out of that airspace but when passing parallel with the building on my side of the street; the app prompted me that I had entered a restricted zone and to promptly exit. So I flew directly away and made brought the sUAS in to land. Confident I did not enter the airspace over the building footprint; I checked to make sure I did not need to report this immediately; then swapped batteries to continue the operation. After the Flight:I have checked my notes from preparing for the Part 107 exam and have not found any relevant notes pertaining to restricted airspace not indicated on the sectional chart. This may be a gap in the regulation that needs to be better taught and tested. I have found online that there may be a regulation to not come within 400 feet of a federal prison but have yet to find a confirming source. From what I have found; this; if true; still would only apply to federal institutions. Closing Statements:The main concern is that I am unaware and uncertain on the regulations related to this county jail. The second concern is that I was unaware of this restricted airspace using two sources before the flight and that the only app to indicate this airspace displayed it incorrectly to my understanding (showed building footprint but notified me that I was in the restricted zone outside of that footprint). I will be looking to contact the controlling agency for authorization for future operations.