Hi @Bernhard S,
I'm assuming this instance doesn't have Domain Separation turned on, since if it does, that's usually the first thing to rule out rather than one item on a list. Answering for that case first, then covering the domain-separated scenario below too.
Your second screenshot shows four Active data collectors with Content source ServiceNow and Calling service DPR Service, so the records themselves are real and correctly configured, nothing wrong on that side. The Add data collector dialog in your first screenshot comes back completely empty though, not even a "no results" message, and you've confirmed it happens on brand-new policies and on ones you already built with existing collectors attached. Records that exist and render fine in a list view but never reach a picker, for every policy, for an admin, points at the query or filter behind that specific dialog rather than at something missing from the platform.
Before chasing anything configuration-side, do the cheap check first: hard refresh the page (or open an incognito window), and if that doesn't change anything, try loading the same policy as a different admin user. This dialog is often driven by a cached client-side list or a stale UI session, and if a different session or a clean cache suddenly shows the collectors, you're done, no further digging needed.
If it's still empty after that, look at the reference qualifier on the field driving that picker. Digital Product Release's policy engine, Policy as Code Engine, is a shared framework other apps plug into as well, and "Calling service" strongly suggests the picker filters data collectors by Calling service plus Content source under the hood. If that qualifier, or something it depends on, got edited or broken by a recent update, it returns zero rows for every user the same way, admin role included.
If Domain Separation is active after all, check whether the policy record and the four data collectors actually sit in the same domain. Admin access to another domain isn't automatic, and the glide.domain.strict_override property specifically changes what an admin session sees even without touching roles. A narrower cousin of the same problem is a company or scope mismatch between the policy and the collector records, since DPR ties records to product and portfolio scoping, worth ruling out separately. A recently changed ACL on the data collector table is less likely here, since your list view already renders those same records for the same user, and list views and picker dialogs typically share the same read ACL, but it's a quick one to eliminate.
Since you mentioned this started after a recent update, it's also worth opening a case on the Now Support portal and searching HI/Known Error for anything logged against Digital Product Release or Policy as Code Engine around your version. I couldn't find a public KB documenting this exact empty-picker symptom, so if there's a PRB behind it, Now Support will have visibility you and I don't from here. Separately, check Skipped Records from that update under System Applications, any local customization on the qualifier or the picker logic would show up there for you to accept or reject rather than get silently overwritten.
Fastest way to actually pin it down: open browser dev tools, Network tab, trigger the dialog, and look at the request it fires. A 200 with an empty array points you at the qualifier or query, a 403 points at ACL, anything else tells its own story.
Let me know what the Network tab shows or which version you're on and I can narrow this down further. If one of these turns out to be it, marking the reply as the accepted solution helps the next person who hits this same empty dialog.
References
Thank you,
Vikram Karety
Octigo Solutions INC
