@mehalufent12199 first try a different memory card. Next follow the instruction provided [https://www.samsung.com/in/support/mobile-devices/how-to-troubleshoot-when-your-device-does-not-detect-an-sd-card/?srsltid=AfmBOooZdzjWH6q6U6dgNjUt6Vww5KpSA1vUWPXP_Hw02W0ho8J0xDVr|by Samsung] for the troubleshooting.
If none of this works then the issues could be related to a bad card reader. If a new card does not work either, you will need to check your card reader. That will require the schematics and board layout files for the SM-M115 as well as special tools and knowledge about a board level repair.