diff --git a/zephyr/prj.conf b/zephyr/prj.conf
index 238b63d..5cffe80 100644
--- a/zephyr/prj.conf
+++ b/zephyr/prj.conf
@@ -11,7 +11,7 @@ CONFIG_MBEDTLS=y
 CONFIG_MBEDTLS_USER_CONFIG_ENABLE=y
 CONFIG_MBEDTLS_USER_CONFIG_FILE="user-tls.conf"
 CONFIG_MBEDTLS_ENABLE_HEAP=y
-CONFIG_MBEDTLS_HEAP_SIZE=4096
+CONFIG_MBEDTLS_HEAP_SIZE=16384
 
 #CONFIG_BT_HCI_TX_STACK_SIZE=1024
 CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=2048