diff --git a/rma_sale/migrations/15.0.1.0.1/post-migration.py b/rma_sale/migrations/15.0.1.0.1/post-migration.py
new file mode 100644
index 00000000..0082eb17
--- /dev/null
+++ b/rma_sale/migrations/15.0.1.0.1/post-migration.py
@@ -0,0 +1,31 @@
+# Part of Hibou Suite Professional. See LICENSE_PROFESSIONAL file for full copyright and licensing details.
+
+import odoo
+
+
+def migrate(cr, version):
+    """
+    Update sale_line_id on existing RMA lines to allow completing the RMA
+    """
+    cr.execute("""
+        UPDATE rma_line AS rl
+        SET sale_line_id = order_line.id
+        FROM (
+            SELECT rma_line.id, rma_line.rma_id, rma_line.product_id,
+                rank() OVER (PARTITION BY rma_line.rma_id, rma_line.product_id ORDER BY rma_line.id) AS rline
+            FROM rma_line
+            WHERE rma_line.sale_line_id IS NULL
+        ) AS rma_line
+        INNER JOIN rma_rma rma 
+            ON rma.id = rma_line.rma_id
+        INNER JOIN (
+            SELECT ol.id, ol.order_id, ol.product_id,
+            rank() OVER (PARTITION BY ol.order_id, ol.product_id ORDER BY ol.id) AS oline
+            FROM sale_order_line ol
+        ) AS order_line
+            ON order_line.order_id = rma.sale_order_id
+            AND order_line.product_id = rma_line.product_id
+            AND order_line.oline = rma_line.rline
+        WHERE rma.sale_order_id IS NOT NULL
+        AND rma_line.id = rl.id
+    """)