diff --git a/models/site.rb b/models/site.rb
index 2779fec3..8801122c 100644
--- a/models/site.rb
+++ b/models/site.rb
@@ -904,7 +904,7 @@ class Site < Sequel::Model
   end
 
   def add_tag_name(name)
-    add_tag Tag.find_or_create(name: name)
+    add_tag Tag.create_unless_exists(name)
   end
 
   def before_create
diff --git a/models/tag.rb b/models/tag.rb
index 6a140317..c744e323 100644
--- a/models/tag.rb
+++ b/models/tag.rb
@@ -17,7 +17,11 @@ class Tag < Sequel::Model
   def self.create_unless_exists(name)
     name = clean_name name
     return nil if name == '' || name.nil?
-    dataset.filter(name: name).first || create(name: name)
+    begin
+      dataset.filter(name: name).first || create(name: name)
+    rescue Sequel::UniqueConstraintViolation
+      dataset.filter(name: name).first
+    end
   end
 
   def self.autocomplete(name, limit=3)