我的firebase函数的推送通知代码如下所示：

//fetch push tokens of all admins as well to send push notification
        var tokens = []

        if(pushToken !== undefined && pushToken !== '')
            tokens.push(pushToken)

        tokens = tokens.concat(adminPushTokens)

        //push tokens need to be of customer as well as all the admins in the system. fetch admin push tokens
        admin.messaging().sendToDevice(tokens, pushPayload).then(
            (resp) => console.log("push notification sent")
        ).catch(
            (err) => console.error("Error sending push notification:" + JSON.stringify(err))
        )

有15-20%的时间

Error sending push notification:{"code":"app/network-timeout","message":"fcm.googleapis.com network timeout. Please try again."}

这对我们来说是一个大问题，不是一个可以接受的表现。我们如何确保提高可靠性？