Can you provide abnormal stack information? I also use offline commands for offline traffic and have not encountered this issue before. Version 3.1.0

It is not an exception. There's no stack information. But I use Arthas to debug the consumer, and then find a cue as the following image. We can see that the filed "services" is a empty array.

The empty "services" cause the "urls 0" problem certainly.

Please try update to 3.2.1.

I'm afraid it is not repaired in 3.2.1.
Step:
first: when we offline an instance, it unexports all the interfaces . what MetadataInfo to do is just remove serviceKey from the array services and mark the "revision" should be updated. but the field "revision" is not really changed. If a request for metadataInfo comes now, it will response the empty services. I think the method getRevision() of MetadataInfo should check whether the filed "updated" is true or not. if true, the method should not return a value. because of the revision can't represent the MetadataInfo now.

public synchronized void removeService(URL url) {
        if (url == null) {
            return;
        }
        this.services.remove(url.getProtocolServiceKey());
        if (exportedServiceURLs != null) {
            removeURL(exportedServiceURLs, url);
        }
        updated = true;
    }
public void unregister(URL url) {
        metadataInfo.removeService(url);
    }