Please try the following:
a. Go to Mobile Settings and select SIM Card & Mobile Networks b. In case of dual SIMS, select the 4G data SIM c. Select Access Point Names d. Select the active APN (Access Point Name) e. Scroll and click on APN Protocol f. Select IPv4 from available options g. Save the APN. (On some mobiles, this option is available at the top-right of the screen.)