From 3f5032614cbb7f3888e98de518c6896ca1510b52 Mon Sep 17 00:00:00 2001
From: Max Kalyabin <maksim@kalyabin.ru>
Date: Tue, 22 Sep 2020 22:51:57 +0300
Subject: [PATCH] fixes #1655 issue

---
 src/PhpSpreadsheet/Reader/Xlsx/Hyperlinks.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/PhpSpreadsheet/Reader/Xlsx/Hyperlinks.php b/src/PhpSpreadsheet/Reader/Xlsx/Hyperlinks.php
index 9e6aeaf788..106fd44efc 100644
--- a/src/PhpSpreadsheet/Reader/Xlsx/Hyperlinks.php
+++ b/src/PhpSpreadsheet/Reader/Xlsx/Hyperlinks.php
@@ -41,7 +41,7 @@ private function setHyperlink(SimpleXMLElement $hyperlink, Worksheet $worksheet)
         foreach (Coordinate::extractAllCellReferencesInRange($hyperlink['ref']) as $cellReference) {
             $cell = $worksheet->getCell($cellReference);
             if (isset($linkRel['id'])) {
-                $hyperlinkUrl = $this->hyperlinks[(string) $linkRel['id']];
+                $hyperlinkUrl = $this->hyperlinks[(string) $linkRel['id']] ?? null;
                 if (isset($hyperlink['location'])) {
                     $hyperlinkUrl .= '#' . (string) $hyperlink['location'];
                 }