diff --git a/compiler/fir/analysis-tests/legacy-fir-tests/tests-gen/org/jetbrains/kotlin/fir/LazyBodyIsNotTouchedTilContractsPhaseTestGenerated.java b/compiler/fir/analysis-tests/legacy-fir-tests/tests-gen/org/jetbrains/kotlin/fir/LazyBodyIsNotTouchedTilContractsPhaseTestGenerated.java
index 698661d6ac2..bde3f0cf9ec 100644
--- a/compiler/fir/analysis-tests/legacy-fir-tests/tests-gen/org/jetbrains/kotlin/fir/LazyBodyIsNotTouchedTilContractsPhaseTestGenerated.java
+++ b/compiler/fir/analysis-tests/legacy-fir-tests/tests-gen/org/jetbrains/kotlin/fir/LazyBodyIsNotTouchedTilContractsPhaseTestGenerated.java
@@ -244,6 +244,11 @@ public class LazyBodyIsNotTouchedTilContractsPhaseTestGenerated extends Abstract
         runTest("compiler/fir/analysis-tests/testData/resolve/implicitTypeInFakeOverride.kt");
     }
 
+    @TestMetadata("incorrectDataClass.kt")
+    public void testIncorrectDataClass() throws Exception {
+        runTest("compiler/fir/analysis-tests/testData/resolve/incorrectDataClass.kt");
+    }
+
     @TestMetadata("incorrectSuperCall.kt")
     public void testIncorrectSuperCall() throws Exception {
         runTest("compiler/fir/analysis-tests/testData/resolve/incorrectSuperCall.kt");
diff --git a/compiler/fir/analysis-tests/testData/resolve/incorrectDataClass.fir.txt b/compiler/fir/analysis-tests/testData/resolve/incorrectDataClass.fir.txt
new file mode 100644
index 00000000000..7ba603cf38d
--- /dev/null
+++ b/compiler/fir/analysis-tests/testData/resolve/incorrectDataClass.fir.txt
@@ -0,0 +1,17 @@
+FILE: incorrectDataClass.kt
+    public final data class Foo : R|kotlin/Any| {
+        public constructor(a: R|kotlin/Int|, b: R|kotlin/Int|): R|Foo| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final val b: R|kotlin/Int| = R|<local>/b|
+            public get(): R|kotlin/Int|
+
+        public final val c: R|kotlin/Int| = Int(4)
+            public get(): R|kotlin/Int|
+
+        public final operator fun component1(): R|kotlin/Int|
+
+        public final fun copy(b: R|kotlin/Int| = this@R|/Foo|.R|/Foo.b|): R|Foo|
+
+    }
diff --git a/compiler/fir/analysis-tests/testData/resolve/incorrectDataClass.kt b/compiler/fir/analysis-tests/testData/resolve/incorrectDataClass.kt
new file mode 100644
index 00000000000..214fca2b270
--- /dev/null
+++ b/compiler/fir/analysis-tests/testData/resolve/incorrectDataClass.kt
@@ -0,0 +1,5 @@
+// ISSUE: KT-44554
+
+data class Foo(a: Int, val b: Int) {
+    val c = 4
+}
diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirDiagnosticTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirDiagnosticTestGenerated.java
index 92d29a5322b..9b2a3b940cd 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirDiagnosticTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirDiagnosticTestGenerated.java
@@ -284,6 +284,12 @@ public class FirDiagnosticTestGenerated extends AbstractFirDiagnosticTest {
             runTest("compiler/fir/analysis-tests/testData/resolve/implicitTypeInFakeOverride.kt");
         }
 
+        @Test
+        @TestMetadata("incorrectDataClass.kt")
+        public void testIncorrectDataClass() throws Exception {
+            runTest("compiler/fir/analysis-tests/testData/resolve/incorrectDataClass.kt");
+        }
+
         @Test
         @TestMetadata("incorrectSuperCall.kt")
         public void testIncorrectSuperCall() throws Exception {
diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirDiagnosticsWithLightTreeTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirDiagnosticsWithLightTreeTestGenerated.java
index 931d3a4966f..f7ad4f2e209 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirDiagnosticsWithLightTreeTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirDiagnosticsWithLightTreeTestGenerated.java
@@ -287,6 +287,12 @@ public class FirDiagnosticsWithLightTreeTestGenerated extends AbstractFirDiagnos
             runTest("compiler/fir/analysis-tests/testData/resolve/implicitTypeInFakeOverride.kt");
         }
 
+        @Test
+        @TestMetadata("incorrectDataClass.kt")
+        public void testIncorrectDataClass() throws Exception {
+            runTest("compiler/fir/analysis-tests/testData/resolve/incorrectDataClass.kt");
+        }
+
         @Test
         @TestMetadata("incorrectSuperCall.kt")
         public void testIncorrectSuperCall() throws Exception {
diff --git a/compiler/fir/raw-fir/psi2fir/src/org/jetbrains/kotlin/fir/builder/RawFirBuilder.kt b/compiler/fir/raw-fir/psi2fir/src/org/jetbrains/kotlin/fir/builder/RawFirBuilder.kt
index 3959e85a96a..214134975b2 100644
--- a/compiler/fir/raw-fir/psi2fir/src/org/jetbrains/kotlin/fir/builder/RawFirBuilder.kt
+++ b/compiler/fir/raw-fir/psi2fir/src/org/jetbrains/kotlin/fir/builder/RawFirBuilder.kt
@@ -862,9 +862,7 @@ class RawFirBuilder(
                         }
 
                         if (classOrObject.hasModifier(DATA_KEYWORD) && firPrimaryConstructor != null) {
-                            val zippedParameters = classOrObject.primaryConstructorParameters.zip(
-                                declarations.filterIsInstance<FirProperty>(),
-                            )
+                            val zippedParameters = classOrObject.primaryConstructorParameters.filter { it.hasValOrVar() } zip declarations.filterIsInstance<FirProperty>()
                             DataClassMembersGenerator(
                                 baseSession,
                                 classOrObject,
@@ -877,7 +875,7 @@ class RawFirBuilder(
                                     // just making a shallow copy isn't enough type ref may be a function type ref
                                     // and contain value parameters inside
                                     withDefaultSourceElementKind(newKind) {
-                                        (property.returnTypeRef.psi as KtTypeReference).toFirOrImplicitType()
+                                        (property.returnTypeRef.psi as KtTypeReference?).toFirOrImplicitType()
                                     }
                                 },
                             ).generate()