Having issues with my whatsapp connectivity

I seem to have some internet issues with WhatsApp and other social media platforms with my wifi, I have recently upgraded to the latest Firmware Version OpenWrt 21.02 everything else seems to work fine. while I tried all the reset and reinstalling the apps etc still no luck. i tried using data and my mate's wifi the apps works just fine. any suggestion/recommendation would be great thanks

What were you running before when it worked?

Thank you for replying, I was running Linksys router official firmware and changed it into the latest openwrt firmware.
(Just to let you know i even went back to my ISP router as a default router from modem mod to router to check if it works but no success..