Handoff/Sync stopped working

I was traveling recently when I noticed that my messages weren't getting handed off to my laptop. The hotel had poor reception. I was unable to get a signal the whole time I was there. However, I thought that once I was outside of the hotel everything would start working again. I often take photos, attach them to a message so that I can drag them to my desktop for editing. I'm unable to do that. I went into settings but I don't seem to be able to find any setting that might have inadvertently gotten turned off. Any ideas? I keep getting Message Failed to send when I try to load photos into messages. However, on my laptop I don't see anything at all. Other messages seem to work.