How to connect the bridge node of painlessmesh to AWS IoT Core to publish message via MQTT?

Background:

I am trying to work with two ESP8266 nodes using the painless mesh. Until now the painless mesh worked fine. At next level i made one of the node as bridge or root node. My intention here now is that the root node should fetch the data from AWS IoT i.e., get subscribed to a topic and get the data and relay the same data to the other child node. Here the protocol i needed to use for communication between the ESP8266 and AWS is MQTT.

As part of connecting to AWS IoT core, i had to use the certificates created for a particular thing in AWS IoT to load it into my root node.

Problem:

Here i am facing an issue saying that the AWS certificates i used to form communication between root node and AWS is "Either expired or not valid". After some research, i found that for SSL certificates to be considered as valid, proper current time stamp has to be considered in the root node. By default the node would have a initial value of the time stamp like year for ex. 1970. To solve this error i used the NTP client and part of the code to force update the time stamp to current time. Still i am facing an issue where the root node is unable to connect to the AWS through MQTT and also the normal painless mesh activity is also affected by this.

I am a beginner to all this concepts regarding painless mesh. Please help me regarding this.
Any suggestion or solution would be very helpful for me.

Thank you.