diff --git a/tests/SolutionErp.Infrastructure.Tests/Services/PurchaseEvaluationWorkflowServiceReturnModeTests.cs b/tests/SolutionErp.Infrastructure.Tests/Services/PurchaseEvaluationWorkflowServiceReturnModeTests.cs
index b59f9b0..a116ca9 100644
--- a/tests/SolutionErp.Infrastructure.Tests/Services/PurchaseEvaluationWorkflowServiceReturnModeTests.cs
+++ b/tests/SolutionErp.Infrastructure.Tests/Services/PurchaseEvaluationWorkflowServiceReturnModeTests.cs
@@ -301,8 +301,11 @@ public class PurchaseEvaluationWorkflowServiceReturnModeTests
             // Audit log "không lùi được" phải xuất hiện ở ContextNote (LogTransitionAsync
             // append summary từ ApplyReturnModeAsync vào field này — line 96-99 service).
             // Summary field cố định "Chuyển phase {from} → {to}".
+            // Plan AB S25 thêm Changelog entry mới (EntityType=Workflow + Summary="Trả lại (...)"
+            // + ContextNote=null) → cùng CreatedAt SQLite tie-break non-deterministic. Filter
+            // by Summary "Chuyển phase" để pick đúng LogTransitionAsync entry.
             var changelog = await db.PurchaseEvaluationChangelogs
-                .Where(c => c.PurchaseEvaluationId == pe.Id)
+                .Where(c => c.PurchaseEvaluationId == pe.Id && c.Summary!.Contains("Chuyển phase"))
                 .OrderByDescending(c => c.CreatedAt)
                 .FirstAsync();
             changelog.ContextNote.Should().NotBeNull();
@@ -343,8 +346,10 @@ public class PurchaseEvaluationWorkflowServiceReturnModeTests
             pe.CurrentApprovalLevelOrder.Should().Be(1, "Pointer reset Cấp 1 (bàn giao về Approver A)");
             pe.SlaDeadline.Should().NotBeNull("SLA reset 7d cho approver mới");
 
+            // Plan AB S25 — thêm Changelog Workflow entry, filter LogTransition entry
+            // qua Summary "Chuyển phase" để pick đúng row có ContextNote.
             var changelog = await db.PurchaseEvaluationChangelogs
-                .Where(c => c.PurchaseEvaluationId == pe.Id)
+                .Where(c => c.PurchaseEvaluationId == pe.Id && c.Summary!.Contains("Chuyển phase"))
                 .OrderByDescending(c => c.CreatedAt)
                 .FirstAsync();
             changelog.ContextNote.Should().NotBeNull();