diff --git a/CHANGELOG.md b/CHANGELOG.md
index 07df59b..197c3a0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+## 1.1.11 (2022-02-05)
+* sheet name maximum length is 31 chars, mb_substr used now
+* license fixed
+
 ## 1.1.10 (2022-02-05)
 * namespace added, use Shuchkin\SimpleXLSXGen
 
diff --git a/license.md b/license.md
index 367e366..162854f 100644
--- a/license.md
+++ b/license.md
@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2014 Lukas Martinelli
+Copyright (c) 2020-2022 Sergey Shuchkin sergey.shuchkin@gmail.com
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/src/SimpleXLSXGen.php b/src/SimpleXLSXGen.php
index 4851e14..ef6f679 100644
--- a/src/SimpleXLSXGen.php
+++ b/src/SimpleXLSXGen.php
@@ -120,6 +120,7 @@ class SimpleXLSXGen {
         if ( $name === null ) { // autogenerated sheet names
             $name = 'Sheet'.($this->curSheet+1);
         } else {
+            $name = mb_substr($name, 0, 31);
             $names = [];
             foreach( $this->sheets as $sh ) {
                 $names[ mb_strtoupper( $sh['name']) ] = 1;