”Warning!” Is not a valid Blynk Event Code, it looks more like an Event Name.
You also have a big problem with the logic around your notification code. Your getSendData function is called once every second, and if the reading from your sensor is >250 for 100 seconds you will have logged 100 events, which is your 24 hour maximum.
Id suggest that you read this (the web console layout has changed slightly since it was written, but the principals are the same)…