diff --git a/src/composable/validation.ts b/src/composable/validation.ts
index 09b1fce4..9d1d4242 100644
--- a/src/composable/validation.ts
+++ b/src/composable/validation.ts
@@ -1,27 +1,30 @@
 import { reactive, watch, type Ref } from 'vue';
 
 type UseValidationRule<T> = {
-  validator: (value: T) => boolean
-  message: string
-}
+  validator: (value: T) => boolean;
+  message: string;
+};
 
 export function useValidation<T>({ source, rules }: { source: Ref<T>; rules: UseValidationRule<T>[] }) {
   const state = reactive<{
-    message: string,
-    status: undefined | 'error'
+    message: string;
+    status: undefined | 'error';
   }>({
     message: '',
-    status: undefined
-  })
+    status: undefined,
+  });
 
   watch([source], () => {
-    for(const rule of rules) {
-      if(!rule.validator(source.value)){
-        state.message = rule.message
-        state.status = 'error'
+    state.message = '';
+    state.status = undefined;
+
+    for (const rule of rules) {
+      if (!rule.validator(source.value)) {
+        state.message = rule.message;
+        state.status = 'error';
       }
     }
-  })
+  });
 
   return state;
 }
diff --git a/src/tools/bip39-generator/bip39-generator.vue b/src/tools/bip39-generator/bip39-generator.vue
index 9f9fc679..87f99428 100644
--- a/src/tools/bip39-generator/bip39-generator.vue
+++ b/src/tools/bip39-generator/bip39-generator.vue
@@ -110,7 +110,7 @@ const entropyValidation = useValidation({
             message: 'Entropy length should be >= 16, <= 32 and be a multiple of 4'
         },
         {
-            validator: (value) => /^[a-fA-f0-9]?$/.test(value),
+            validator: (value) => /^[a-fA-F0-9]*$/.test(value),
             message: 'Entropy should an hexadecimal number'
         }
     ]