diff --git a/test/WireMock.Net.Tests/Matchers/SystemTextJsonMatcherTests.cs b/test/WireMock.Net.Tests/Matchers/SystemTextJsonMatcherTests.cs
index cbc7ba73..6a97284a 100644
--- a/test/WireMock.Net.Tests/Matchers/SystemTextJsonMatcherTests.cs
+++ b/test/WireMock.Net.Tests/Matchers/SystemTextJsonMatcherTests.cs
@@ -68,9 +68,10 @@ public class SystemTextJsonMatcherTests
     {
         // Assign
         var matcher = new SystemTextJsonMatcher("{}");
+        using var stream = new MemoryStream();
 
         // Act
-        var result = matcher.IsMatch(new MemoryStream());
+        var result = matcher.IsMatch(stream);
 
         // Assert
         result.Score.Should().Be(MatchScores.Mismatch);
diff --git a/test/WireMock.Net.Tests/Matchers/SystemTextJsonPartialWildcardMatcherTests.cs b/test/WireMock.Net.Tests/Matchers/SystemTextJsonPartialWildcardMatcherTests.cs
index f5d936a7..057a9ecd 100644
--- a/test/WireMock.Net.Tests/Matchers/SystemTextJsonPartialWildcardMatcherTests.cs
+++ b/test/WireMock.Net.Tests/Matchers/SystemTextJsonPartialWildcardMatcherTests.cs
@@ -60,7 +60,8 @@ public class SystemTextJsonPartialWildcardMatcherTests
         var matcher = new SystemTextJsonPartialWildcardMatcher("{}");
 
         // Act
-        var result = matcher.IsMatch(new MemoryStream());
+        using var stream = new MemoryStream();
+        var result = matcher.IsMatch(stream);
 
         // Assert
         result.Score.Should().Be(MatchScores.Mismatch);