The problems started around 5:30 p.m. yesterday afternoon. It seemed to be resolved for a while, but that turned out not to be the case around 8 p.m. As a result, no train traffic was possible to and from Amsterdam Central this morning either.
There were also no trains running from Amsterdam to Haarlem, Schiphol, Zaandam and Weesp this morning. Fewer or no trains ran to the other train stations in the province.