diff --git a/api/src/main/java/org/openmrs/module/queue/api/digitalSignage/QueueTicketAssignments.java b/api/src/main/java/org/openmrs/module/queue/api/digitalSignage/QueueTicketAssignments.java
index 5359633..b7d769d 100644
--- a/api/src/main/java/org/openmrs/module/queue/api/digitalSignage/QueueTicketAssignments.java
+++ b/api/src/main/java/org/openmrs/module/queue/api/digitalSignage/QueueTicketAssignments.java
@@ -11,6 +11,7 @@
 
 import java.util.HashMap;
 import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 
 import lombok.extern.slf4j.Slf4j;
 import org.apache.commons.lang3.StringUtils;
@@ -25,7 +26,7 @@ public class QueueTicketAssignments {
 	 * The object has: service point/room name as key for ease of search and update and object with
 	 * status and ticket number
 	 */
-	private static final Map<String, TicketAssignment> ACTIVE_QUEUE_TICKETS = new HashMap<>();
+	private static final Map<String, TicketAssignment> ACTIVE_QUEUE_TICKETS = new ConcurrentHashMap<>();
 	
 	/**
 	 * We want to control access to the ACTIVE_QUEUE_TICKETS so that requests are queued
diff --git a/api/src/main/resources/liquibase.xml b/api/src/main/resources/liquibase.xml
index 5e4c38b..2081369 100644
--- a/api/src/main/resources/liquibase.xml
+++ b/api/src/main/resources/liquibase.xml
@@ -749,4 +749,27 @@
         </sql>
     </changeSet>
 
+    <changeSet id="add_visit_queue_number_attribute_type_20260521" author="ujjawalprabhat">
+        <preConditions onFail="MARK_RAN">
+            <sqlCheck expectedResult="0">
+                SELECT COUNT(*) FROM visit_attribute_type WHERE uuid = 'c0c579b0-8e59-401d-8a4a-976a0b183519';
+            </sqlCheck>
+        </preConditions>
+        <comment>
+            Insert the "Visit Queue Number" visit attribute type used by the queue screen to display ticket numbers.
+            UUID matches the default value of `visitQueueNumberAttributeUuid` in @openmrs/esm-service-queues-app.
+        </comment>
+        <insert tableName="visit_attribute_type">
+            <column name="name" value="Visit Queue Number"/>
+            <column name="description" value="The visit queue number used to identify patients on the queue screen"/>
+            <column name="datatype" value="org.openmrs.customdatatype.datatype.FreeTextDatatype"/>
+            <column name="min_occurs" valueNumeric="0"/>
+            <column name="max_occurs" valueNumeric="1"/>
+            <column name="creator" valueNumeric="1"/>
+            <column name="date_created" valueComputed="NOW()"/>
+            <column name="retired" valueBoolean="false"/>
+            <column name="uuid" value="c0c579b0-8e59-401d-8a4a-976a0b183519"/>
+        </insert>
+    </changeSet>
+
 </databaseChangeLog>