diff --git a/src/Psalm/Internal/Analyzer/Statements/Expression/Call/ArgumentAnalyzer.php b/src/Psalm/Internal/Analyzer/Statements/Expression/Call/ArgumentAnalyzer.php
index 19a075ffe..f566002c4 100644
--- a/src/Psalm/Internal/Analyzer/Statements/Expression/Call/ArgumentAnalyzer.php
+++ b/src/Psalm/Internal/Analyzer/Statements/Expression/Call/ArgumentAnalyzer.php
@@ -491,6 +491,8 @@ class ArgumentAnalyzer
                         && isset($unpacked_atomic_array->properties[$unpacked_argument_offset])
                     ) {
                         $arg_value_type = $unpacked_atomic_array->properties[$unpacked_argument_offset];
+                    } elseif ($unpacked_atomic_array->fallback_params) {
+                        $arg_value_type = $unpacked_atomic_array->getGenericValueType();
                     } elseif ($function_param->is_optional && $function_param->default_type) {
                         if ($function_param->default_type instanceof Union) {
                             $arg_value_type = $function_param->default_type;
diff --git a/tests/Template/ClassTemplateTest.php b/tests/Template/ClassTemplateTest.php
index a99c5d46f..677c078ba 100644
--- a/tests/Template/ClassTemplateTest.php
+++ b/tests/Template/ClassTemplateTest.php
@@ -4564,7 +4564,7 @@ class ClassTemplateTest extends TestCase
 
                     $m = new Map(fn(int $num) => (string) $num);
                     $m(["a"]);',
-                'error_message' => 'InvalidScalarArgument',
+                'error_message' => 'InvalidArgument',
                 'ignored_issues' => [],
                 'php_version' => '8.0'
             ],