diff --git a/app/src/main/java/io/legado/app/service/DownloadService.kt b/app/src/main/java/io/legado/app/service/DownloadService.kt
index 13b55ac13..bbe44141c 100644
--- a/app/src/main/java/io/legado/app/service/DownloadService.kt
+++ b/app/src/main/java/io/legado/app/service/DownloadService.kt
@@ -184,9 +184,7 @@ class DownloadService : BaseService() {
                         scope = this,
                         context = searchPool
                     ).onError {
-                        it.localizedMessage?.let {
-                            Download.addLog(it)
-                        }
+                        Download.addLog(it.localizedMessage)
                     }.onSuccess(IO) { content ->
                         downloadCount[book.bookUrl]?.increaseSuccess()
                         BookHelp.saveContent(book, bookChapter, content)
diff --git a/app/src/main/java/io/legado/app/service/help/Download.kt b/app/src/main/java/io/legado/app/service/help/Download.kt
index 844f127b2..d7e99b641 100644
--- a/app/src/main/java/io/legado/app/service/help/Download.kt
+++ b/app/src/main/java/io/legado/app/service/help/Download.kt
@@ -9,7 +9,8 @@ object Download {
 
     val logs = arrayListOf<String>()
 
-    fun addLog(log: String) {
+    fun addLog(log: String?) {
+        log ?: return
         synchronized(this) {
             if (logs.size > 30) {
                 logs.removeAt(0)