I think slow internet connection is the main cause of such problems. I also faced same problem when my internet connection goes slow. Specially at the pick hour in country this types of slow connection are found here. When internet connection becomes faster after a while then the problem is solved. so I also faced same problem when my internet connection goes slow , so same here that you have a slow or bad internet connection which is delaying your orders from communication quickly with the server so must try to get a better internet connection now.