Is MBEDTLS date/time is not supported in nRF security ?
warning: MBEDTLS_HAVE_TIME_DATE (defined at modules/mbedtls/Kconfig.tls-generic:458, modules/mbedtls/Kconfig.tls-generic:458) was assigned the value 'y' but got the value 'n'. Check these unsatisfied dependencies: ((MBEDTLS_BUILTIN && MBEDTLS_CFG_FILE = "config-tls-generic.h" && MBEDTLS) || (MBEDTLS_BUILTIN && MBEDTLS_CFG_FILE = "config-tls-generic.h" && MBEDTLS && 0)) (=n). See http://docs.zephyrproject.org/latest/kconfig.html#CONFIG_MBEDTLS_HAVE_TIME_DATE and/or look up MBEDTLS_HAVE_TIME_DATE in the menuconfig/guiconfig interface. The Application Development Primer, Setting Configuration Values, and Kconfig - Tips and Best Practices sections of the manual might be helpful too.
We would like to have certificate validity check, but unable to enable it.