Blynk not connecting?

Have you rebooted your router?

Have you tried downgrading to 1.0.1 to eliminate that as a potential issue?

That sounds like a very unsatisfactory hardware arrangement. What is the Arduino doing that couldn’t be done by the NodeMCU?

Your problem is that your NodeMCU’s hardware serial port is being used for communication with the Arduino, and that is preventing you from using it for debugging the connection issue with the Blynk server. If you could see the Blynk debug messages they would almost certainly give you a clue about where the issue lies.

I’d do everything I could to eliminate the Arduino from the equation, and if that really isn’t possible then I’d connect the Arduino to a SoftwareSerial port on the NodeMCU, or create a SoftwareSerial port for debugging and use an FTDI adapter.

The message you received was almost certainly that you’d reached your EVENT limit, not NOTIFICATION limit.
This will be because you haven’t set-up the notification correctly, and because you don’t have any way to prevent multiple events from being triggered for the same alarm situation. This would normally be done us8ng a flag variable.

Once you get connected again you should read this…