diff --git a/android/src/main/java/com/jimmydaddy/imagemarker/base/ErrorCode.kt b/android/src/main/java/com/jimmydaddy/imagemarker/base/ErrorCode.kt
index f81cdb9d..2aae1083 100644
--- a/android/src/main/java/com/jimmydaddy/imagemarker/base/ErrorCode.kt
+++ b/android/src/main/java/com/jimmydaddy/imagemarker/base/ErrorCode.kt
@@ -4,5 +4,6 @@ enum class ErrorCode(val value: String) {
   INVALID_PARAMS("INVALID_PARAMS"),
   LOAD_IMAGE_FAILED("LOAD_IMAGE_FAILED"),
   GET_RESOURCE_FAILED("GET_RESOURCE_FAILED"),
-  PARAMS_REQUIRED("PARAMS_REQUIRED");
+  PARAMS_REQUIRED("PARAMS_REQUIRED"),
+  NULL_MAP("NULL_MAP");
 }
diff --git a/android/src/main/java/com/jimmydaddy/imagemarker/base/MarkTextOptions.kt b/android/src/main/java/com/jimmydaddy/imagemarker/base/MarkTextOptions.kt
index 31b3043b..6093d27a 100644
--- a/android/src/main/java/com/jimmydaddy/imagemarker/base/MarkTextOptions.kt
+++ b/android/src/main/java/com/jimmydaddy/imagemarker/base/MarkTextOptions.kt
@@ -12,7 +12,11 @@ class MarkTextOptions(options: ReadableMap) : Options(options) {
       watermarkTexts = arrayOfNulls(waterMarkTextsMap.size())
       for (i in 0 until waterMarkTextsMap.size()) {
         val textMap = waterMarkTextsMap.getMap(i)
-        watermarkTexts[i] = TextOptions(textMap)
+        textMap?.let {
+          watermarkTexts[i] = TextOptions(it)
+        } ?: run {
+          throw MarkerError(ErrorCode.NULL_MAP, "watermarkTexts[$i] is null")
+        }
       }
     }
   }
diff --git a/android/src/main/java/com/jimmydaddy/imagemarker/base/Utils.kt b/android/src/main/java/com/jimmydaddy/imagemarker/base/Utils.kt
index 9c81ce66..384e4509 100644
--- a/android/src/main/java/com/jimmydaddy/imagemarker/base/Utils.kt
+++ b/android/src/main/java/com/jimmydaddy/imagemarker/base/Utils.kt
@@ -163,8 +163,8 @@ class Utils {
       return if (d == null) "0"
       else
           when (d.type) {
-            ReadableType.String -> d.asString()
-            ReadableType.Number -> d.asDouble().toString()
+            ReadableType.String -> d.asString()!!
+            ReadableType.Number -> d.asDouble().toString()!!
             else -> {
               "0"
             }