diff --git a/CHANGELOG.md b/CHANGELOG.md
index 31ecc436..93132a7b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Fix pugx badges in README ([#742](https://github.com/jsonrainbow/json-schema/pull/742))
 - Add missing property in UriResolverTest ([#743](https://github.com/jsonrainbow/json-schema/pull/743))
 - Correct casing of paths used in tests ([#745](https://github.com/jsonrainbow/json-schema/pull/745))
+- Resolve deprecations of optional parameter ([#752](https://github.com/jsonrainbow/json-schema/pull/752))
 
 ### Changed
 - Bump to minimum PHP 7.2 ([#746](https://github.com/jsonrainbow/json-schema/pull/746))
diff --git a/src/JsonSchema/Constraints/Constraint.php b/src/JsonSchema/Constraints/Constraint.php
index bc20e97b..2390bf90 100644
--- a/src/JsonSchema/Constraints/Constraint.php
+++ b/src/JsonSchema/Constraints/Constraint.php
@@ -40,7 +40,7 @@ abstract class Constraint extends BaseConstraint implements ConstraintInterface
      *
      * @return JsonPointer;
      */
-    protected function incrementPath(?JsonPointer $path = null, $i)
+    protected function incrementPath(?JsonPointer $path, $i)
     {
         $path = $path ?: new JsonPointer('');
 
diff --git a/src/JsonSchema/Constraints/ObjectConstraint.php b/src/JsonSchema/Constraints/ObjectConstraint.php
index 36daf77d..5b7d1d00 100644
--- a/src/JsonSchema/Constraints/ObjectConstraint.php
+++ b/src/JsonSchema/Constraints/ObjectConstraint.php
@@ -52,7 +52,7 @@ public function check(&$element, $schema = null, ?JsonPointer $path = null, $pro
         $this->validateElement($element, $matches, $schema, $path, $properties, $additionalProp);
     }
 
-    public function validatePatternProperties($element, ?JsonPointer $path = null, $patternProperties)
+    public function validatePatternProperties($element, ?JsonPointer $path, $patternProperties)
     {
         $matches = [];
         foreach ($patternProperties as $pregex => $schema) {