I work with a asp.net core (ABP) backend on daily basis, and many of our Dto's use DataAnnotation to require fields or limit inputs. These last days however, we've experienced that endpoints suddenly deny access from our angular frontend, which have previously worked fine, but now it won't even enter the controller in debug mode, and only shows a failed request has been made. We can fix it by removing DataAnnotation fields, but it's a nice feature, that we'd like to keep.
Does anyone have a plausible explanation for the sudden change, or where to look for discrepancies?
