diff --git a/app/controllers/concerns/epp/common.rb b/app/controllers/concerns/epp/common.rb
index d43b82190..f5cb2e33e 100644
--- a/app/controllers/concerns/epp/common.rb
+++ b/app/controllers/concerns/epp/common.rb
@@ -63,6 +63,19 @@ module Epp::Common
     @errors += obj.errors[:epp_errors]
   end
 
+  def epp_request_valid?(*selectors)
+    selectors.each do |selector|
+      el = parsed_frame.css(selector).first
+      next unless el
+      epp_errors << {
+        code: '2003',
+        msg: I18n.t('errors.messages.required_parameter_missing', key: el.name)
+      } unless el.text.present?
+    end
+
+    epp_errors.empty?
+  end
+
   def xml_attrs_present?(ph, attributes)
     attributes.each do |x|
       epp_errors << {
diff --git a/app/helpers/epp/keyrelay_helper.rb b/app/helpers/epp/keyrelay_helper.rb
index f1b12ae5c..f879621f4 100644
--- a/app/helpers/epp/keyrelay_helper.rb
+++ b/app/helpers/epp/keyrelay_helper.rb
@@ -1,30 +1,54 @@
 module Epp::KeyrelayHelper
+  # rubocop: disable Metrics/PerceivedComplexity
+  # rubocop: disable Metrics/CyclomaticComplexity
+
   def keyrelay
-    domain = Domain.find_by(name: parsed_frame.css('name').text)
+    handle_errors and return unless validate_keyrelay_request
 
-    abs_datetime = parsed_frame.css('absolute').text
-    abs_datetime = abs_datetime.to_date if abs_datetime
+    @domain = find_domain
 
-    kr = domain.keyrelays.create(
-      domain: domain,
-      pa_date: Time.now,
-      key_data_flags: parsed_frame.css('flags').text,
-      key_data_protocol: parsed_frame.css('protocol').text,
-      key_data_alg: parsed_frame.css('alg').text,
-      key_data_public_key: parsed_frame.css('pubKey').text,
-      auth_info_pw: parsed_frame.css('pw').text,
-      expiry_relative: parsed_frame.css('relative').text,
-      expiry_absolute: abs_datetime,
-      requester: current_epp_user.registrar,
-      accepter: domain.registrar
-    )
-
-    domain.registrar.messages.create(
-      body: 'Key Relay action completed successfully.',
-      attached_obj_type: kr.class.to_s,
-      attached_obj_id: kr.id
-    )
+    handle_errors(@domain) and return unless @domain
+    handle_errors(@domain) and return unless @domain.authenticate(parsed_frame.css('pw').text)
+    handle_errors(@domain) and return unless @domain.keyrelay(parsed_frame, current_epp_user.registrar)
 
     render '/epp/shared/success'
   end
+  # rubocop: enable Metrics/PerceivedComplexity
+  # rubocop: enable Metrics/CyclomaticComplexity
+
+  private
+
+  def validate_keyrelay_request
+    epp_request_valid?('pubKey', 'flags', 'protocol', 'algorithm', 'name', 'pw')
+
+    if parsed_frame.css('relative').text.present? && parsed_frame.css('absolute').text.present?
+      epp_errors << {
+        code: '2003',
+        msg: I18n.t('only_one_parameter_allowed', param_1: 'relative', param_2: 'absolute')
+      }
+    elsif parsed_frame.css('relative').text.empty? && parsed_frame.css('absolute').text.empty?
+      epp_errors << {
+        code: '2003',
+        msg: I18n.t('required_parameter_missing_choice', param_1: 'relative', param_2: 'absolute')
+      }
+    end
+
+    epp_errors.empty?
+  end
+
+  def find_domain
+    domain_name = parsed_frame.css('name').text.strip.downcase
+    domain = Epp::EppDomain.find_by(name: domain_name)
+
+    unless domain
+      epp_errors << {
+        code: '2303',
+        msg: I18n.t('errors.messages.epp_domain_not_found'),
+        value: { obj: 'name', val: domain_name }
+      }
+      return nil
+    end
+
+    domain
+  end
 end
diff --git a/app/models/epp/epp_domain.rb b/app/models/epp/epp_domain.rb
index a7f27314d..ea768824a 100644
--- a/app/models/epp/epp_domain.rb
+++ b/app/models/epp/epp_domain.rb
@@ -357,6 +357,38 @@ class Epp::EppDomain < Domain
     save(validate: false)
   end
 
+  def keyrelay(parsed_frame, requester)
+    if registrar == requester
+      errors.add(:base, :domain_already_belongs_to_the_querying_registrar) and return false
+    end
+
+    abs_datetime = parsed_frame.css('absolute').text
+    abs_datetime = abs_datetime.to_date if abs_datetime
+
+    transaction do
+      kr = keyrelays.create(
+        pa_date: Time.now,
+        key_data_flags: parsed_frame.css('flags').text,
+        key_data_protocol: parsed_frame.css('protocol').text,
+        key_data_alg: parsed_frame.css('alg').text,
+        key_data_public_key: parsed_frame.css('pubKey').text,
+        auth_info_pw: parsed_frame.css('pw').text,
+        expiry_relative: parsed_frame.css('relative').text,
+        expiry_absolute: abs_datetime,
+        requester: requester,
+        accepter: registrar
+      )
+
+      registrar.messages.create(
+        body: 'Key Relay action completed successfully.',
+        attached_obj_type: kr.class.to_s,
+        attached_obj_id: kr.id
+      )
+
+      kr
+    end
+  end
+
   ### VALIDATIONS ###
 
   def validate_exp_dates(cur_exp_date)
diff --git a/config/locales/en.yml b/config/locales/en.yml
index 2d785280d..41f08825b 100644
--- a/config/locales/en.yml
+++ b/config/locales/en.yml
@@ -426,3 +426,5 @@ en:
   host_obj_is_not_allowed: 'hostObj object is not allowed'
   generate_zonefile: 'Generate zonefile'
   zonefile: 'Zonefile'
+  only_one_parameter_allowed: 'Only one parameter allowed: %{param_1} or %{param_2}'
+  required_parameter_missing_choice: 'Required parameter missing: %{param_1} or %{param_2}'
diff --git a/spec/epp/keyrelay_spec.rb b/spec/epp/keyrelay_spec.rb
index 50696b120..bcdcddd6b 100644
--- a/spec/epp/keyrelay_spec.rb
+++ b/spec/epp/keyrelay_spec.rb
@@ -39,6 +39,5 @@ describe 'EPP Keyrelay', epp: true do
 
       expect(zone.messages.queued.count).to eq(1)
     end
-
   end
 end