diff --git a/lib/validates_overlap/overlap_validator.rb b/lib/validates_overlap/overlap_validator.rb
index 5ac19f0..97fc83b 100644
--- a/lib/validates_overlap/overlap_validator.rb
+++ b/lib/validates_overlap/overlap_validator.rb
@@ -182,7 +182,7 @@ def resolve_attribute_value(record, attr_name, value = nil)
       value = record.read_attribute(attr_name)
 
       if is_enum_attribute?(record, attr_name)
-        value = record.class.defined_enums[attr_name][value]
+        value = record.class.defined_enums[attr_name.to_s][value]
       end
 
       value