It's been happening to me a lot, last time was this morning. Pokestops are dead if you travel over 20mph but I too had one not even spin at all, also getting super annoyed at all the sightings vanishing and taking so long to return S:
I've been getting fewer revives not only that but I had a decent amount of max revives and a good chunk of them disappeared. I noticed when I went to use them. I dunno it's crazy.
Finally saw Lapras but it was gone by the time I got there. I boogied too. So many sads ::HMM::