diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8a4d902a..2d8558cd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,7 +18,7 @@
 - Minor: Added a setting to show the stream title in live messages. (#6572)
 - Minor: Add categories to the emoji viewer. (#6598)
 - Minor: Added broadcaster-only `/poll`, `/cancelpoll`, and `/endpoll` commands. (#6583, #6605)
-- Minor: Added broadcaster-only `/prediction`, `/cancelprediction`, `/lockprediction`, and `/completeprediction` commands. (#6583, #6612, #6632)
+- Minor: Added broadcaster-only `/prediction`, `/cancelprediction`, `/lockprediction`, and `/completeprediction` commands. (#6583, #6612, #6632, #6749)
 - Minor: Added support for BetterTTV Pro subscriber badges. (#6625, #6724)
 - Minor: Added `debug.traceback` for plugins. (#6652)
 - Minor: Added title and duration options for `/clip` command. (#6669)
diff --git a/src/controllers/commands/builtin/twitch/Prediction.cpp b/src/controllers/commands/builtin/twitch/Prediction.cpp
index f400ba21..82b32c48 100644
--- a/src/controllers/commands/builtin/twitch/Prediction.cpp
+++ b/src/controllers/commands/builtin/twitch/Prediction.cpp
@@ -280,7 +280,7 @@ QString completePrediction(const CommandContext &ctx)
         return "";
     }
 
-    int targetIndex = 0;
+    size_t targetIndex = 0;
     QString targetName;
     if (hasName)
     {
@@ -289,8 +289,8 @@ QString completePrediction(const CommandContext &ctx)
     else
     {
         bool ok = true;
-        targetIndex = parser.value(indexOption).toInt(&ok);
-        if (!ok || targetIndex <= 0)
+        targetIndex = parser.value(indexOption).toULongLong(&ok);
+        if (!ok || targetIndex == 0)
         {
             ctx.channel->addSystemMessage("Invalid index - " + usage);
             return "";