diff --git a/composer.json b/composer.json
index 4914f2c..2dea6ee 100644
--- a/composer.json
+++ b/composer.json
@@ -4,7 +4,7 @@
   "minimum-stability": "stable",
   "license": "proprietary",
   "require": {
-    "php": ">=7.2",
+    "php": ">=7.4",
     "ext-json": "*"
   },
   "authors": [
diff --git a/src/Rdap.php b/src/Rdap.php
index 1c04bce..76d6433 100644
--- a/src/Rdap.php
+++ b/src/Rdap.php
@@ -128,7 +128,7 @@ public function search(string $search): ?RdapResponse {
                     // exact match
                     if ($number === $parameter) {
                         // check for slash as last character in the server name, if not, add it
-                        if ($service[1][0]{strlen($service[1][0]) - 1} !== '/') {
+                        if ($service[1][0][strlen($service[1][0]) - 1] !== '/') {
                             $service[1][0] .= '/';
                         }