scrolling the bar to the top once, but onYReachStart() is triggered multiple times?

When I scroll the bar just once to the top to load more messages, onYReachStart() is triggered multiple times. Meanwhile, when I first click the chat user (if I don't click, I won't see the chat page), the chat page shows and onYReachStart() is triggered once automatically. My onYReachStart() code is as below ( this.state.noMoreMessages === true if there is no more messages to load and vice versa ):

 async onYReachStart(e) {
        console.log('YReachStart!!!!!!', this.state.loadingMore, this.state.noMoreMessages); // if onYReachStart is triggered, you'll see this line
        if (this.state.loadingMore) {
            return;
        }
        // this.setState({loadingMore: true});
        if (this.state.noMoreMessages === false) {

            await fetch('http://192.168.2.94:8585/httpserver/testing', {
                method: 'POST',
                headers: new Headers({'content-type' : 'application/json'}),
                body: JSON.stringify({
                    mode: 'history1',
                    id: this.state.portId,
                    num: this.getCount(this.state.msgDataList, this.state.loadedMsgList)
                })
            })
            .then (res => res.json())
            .then (data => {
                console.log(data);
                const received_loaded_messages = data.information;
                this.setState({noMoreMessages: data.no_more_message});

                var messages = [];
                let list = received_loaded_messages;
                list.reverse().forEach((val, i) => {
                  messages.push(
                      <Message model={{ direction: position }}>
                          <Message.TextContent text={val.information} />
                      </Message>
                  )

                this.setState({
                    loadedMsgList: messages.reverse().concat(this.state.loadedMsgList),
                    loadingMore: false
                });
            })
            .catch(function (error) {
            console.log(error);
        });
        } else {return;}
    }

chatscope / chat-ui-kit-react

scrolling the bar to the top once, but onYReachStart() is triggered multiple times? #78