Node Red Error : Received msg before firebase.once() node was ready. Not processing:

Hi,
I have a firebase real-time database and node red service which is running perfectly but suddenly it stopped working and showing error like "Received msg before firebase.once() node was ready. Not processing:". At the moment this error occurs, node service is crashed!!
please advise on this issue. I was unable to get any solutions for this issue on internet please explain the root cause of this issue and also suggest me a solution for this.
thanks in advance.

Node-Red Version : v1.2.5
Node - Version : v12.18.2
Firebase-Node : node-red-contrib-firebase