diff --git a/app/services/invoices/apply_provider_taxes_service.rb b/app/services/invoices/apply_provider_taxes_service.rb
index 87c86a1d73f..5e25a3e7c64 100644
--- a/app/services/invoices/apply_provider_taxes_service.rb
+++ b/app/services/invoices/apply_provider_taxes_service.rb
@@ -124,7 +124,7 @@ def fetch_provider_taxes_result
     def calculate_key(tax)
       tax_rate = tax.rate.is_a?(String) ? tax.rate.to_f * 100 : tax.rate
 
-      "#{tax.type}-#{tax.name.parameterize(separator: '_')}-#{tax_rate.to_s}"
+      "#{tax.type}-#{tax.name.parameterize(separator: "_")}-#{tax_rate}"
     end
   end
 end
diff --git a/db/migrate/20240708195226_remove_null_constraint_on_applied_taxes.rb b/db/migrate/20240708195226_remove_null_constraint_on_applied_taxes.rb
index bbc0ba7cbc7..d2a3cefdc0b 100644
--- a/db/migrate/20240708195226_remove_null_constraint_on_applied_taxes.rb
+++ b/db/migrate/20240708195226_remove_null_constraint_on_applied_taxes.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class RemoveNullConstraintOnAppliedTaxes < ActiveRecord::Migration[7.1]
   def change
     change_column_null :fees_taxes, :tax_id, true
diff --git a/spec/services/invoices/apply_provider_taxes_service_spec.rb b/spec/services/invoices/apply_provider_taxes_service_spec.rb
index 61045bd5526..c98079884f7 100644
--- a/spec/services/invoices/apply_provider_taxes_service_spec.rb
+++ b/spec/services/invoices/apply_provider_taxes_service_spec.rb
@@ -26,7 +26,7 @@
     [
       OpenStruct.new(
         tax_breakdown: [
-          OpenStruct.new(name: 'tax 1', type: 'type1', rate: '0.10'),
+          OpenStruct.new(name: 'tax 1', type: 'type1', rate: '0.10')
         ]
       ),
       OpenStruct.new(