Update more then one time problem

hi, when i try to update one row 2 time i get problem

/src/app/pages/examples/server/advanced-example-server.component.ts

ERROR Error: Uncaught (in promise): Error: Element was not found in the dataset
Error: Element was not found in the dataset
at ServerDataSource.find (local.data-source.ts:71)
at local.data-source.ts:58
at new ZoneAwarePromise (zone-evergreen.js:960)
at ServerDataSource.update (local.data-source.ts:57)
at grid.ts:152
at ZoneDelegate.invoke (zone-evergreen.js:364)
at Object.onInvoke (core.js:27486)
at ZoneDelegate.invoke (zone-evergreen.js:363)
at Zone.run (zone-evergreen.js:123)
at zone-evergreen.js:857
at resolvePromise (zone-evergreen.js:798)
at resolvePromise (zone-evergreen.js:750)
at zone-evergreen.js:860
at ZoneDelegate.invokeTask (zone-evergreen.js:399)
at Object.onInvokeTask (core.js:27474)
at ZoneDelegate.invokeTask (zone-evergreen.js:398)
at Zone.runTask (zone-evergreen.js:167)
at drainMicroTaskQueue (zone-evergreen.js:569)
at ZoneTask.invokeTask [as invoke] (zone-evergreen.js:484)
at invokeTask (zone-evergreen.js:1621)