# \[SOLVED\] Stop cheating in QR scanner app **URL:** \ **Category:** Questions about Thunkable X\ **Created:** [June 19, 2024, 8:24am UTC](https://community.thunkable.com/t/solved-stop-cheating-in-qr-scanner-app/3064388 "2024-06-19T08:24:15Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![nuuzonessqnzvv](https://avatars.discourse-cdn.com/v4/letter/n/bbce88/32.png) [@nuuzonessqnzvv](https://community.thunkable.com/u/nuuzonessqnzvv)\ **Post date:** [June 19, 2024, 8:24am UTC](https://community.thunkable.com/t/solved-stop-cheating-in-qr-scanner-app/3064388/1 "2024-06-19T08:24:15Z")
Hi all, I am using the QR code scanner function for a scavenger hunt app. I have the app ready to scan QR codes with the value, tag 1, tag 2 & tag 3, (seen below). ![Screenshot 2024-06-19 084517](https://us1.discourse-cdn.com/flex015/uploads/thunkable/original/3X/e/6/e6d38c554745809a6874abc22340bd3c8c1f8263.png) I want to make sure people do not cheat by scanning one QR code multiple times to proceed to the next stage. The user should be able to scan ‘Tag 1’ once, but after that if they attempt to scan it again then it leads to an error message, or something prompting that they have tried to cheat. I have been going back and forward with this and struggling as the ‘Tag 1, Tag 2, Tag 3’ values are text and can not be stored in a list. So far I have got an error label to work if the value is not in the table, (blocks below), but this does not help if someone was to just scan Tag 1 many times to proceed. ![Screenshot 2024-06-19 091241](https://us1.discourse-cdn.com/flex015/uploads/thunkable/original/3X/5/4/54516e6e26b6d859061b9bc2f8860b92684774bd.png) Any help or ideas would be greatly appreciated. Thank you ---
**Author:** ![ioannis](https://sea1.discourse-cdn.com/flex015/user_avatar/community.thunkable.com/ioannis/32/146956_2.png) [@ioannis](https://community.thunkable.com/u/ioannis)\ **Post date:** [June 20, 2024, 7:00pm UTC](https://community.thunkable.com/t/solved-stop-cheating-in-qr-scanner-app/3064388/2 "2024-06-20T19:00:19Z")
Hello @nuuzonessqnzvv Thank you for sharing all the details To prevent users from scanning the same tag many times I suggest adding a variable that is a list and every time they scan a tag add it on that list. Then you need to add an extra condition to check if the variable list contains the tag. ---
**Author:** ![nuuzonessqnzvv](https://avatars.discourse-cdn.com/v4/letter/n/bbce88/32.png) [@nuuzonessqnzvv](https://community.thunkable.com/u/nuuzonessqnzvv)\ **Post date:** [June 20, 2024, 7:04pm UTC](https://community.thunkable.com/t/solved-stop-cheating-in-qr-scanner-app/3064388/3 "2024-06-20T19:04:16Z")
Thank you @ioannis Issue all resolved, cheers 🙂 ---
**Author:** ![ioannis](https://sea1.discourse-cdn.com/flex015/user_avatar/community.thunkable.com/ioannis/32/146956_2.png) [@ioannis](https://community.thunkable.com/u/ioannis)\ **Post date:** [June 20, 2024, 7:05pm UTC](https://community.thunkable.com/t/solved-stop-cheating-in-qr-scanner-app/3064388/4 "2024-06-20T19:05:34Z")