Flickr has become seriously unreliable in the last year or two as Yahoo enters its death spiral and the vulture investors circle. Wait for a couple minutes, then try again. If you still get an error, wait for an hour or two, try again. Then wait for a day. Invariable the issue goes away. See this topic in the official Adobe feedback forum: Lightroom: Can't update this collection: Semi Colon Expected. If publishing your photos is business-critical, consider another service.