# Unexpected Application Error! **URL:** \ **Category:** Issues / Bugs\ **Tags:** help\ **Created:** [November 2, 2024, 5:35pm UTC](https://community.thunkable.com/t/unexpected-application-error/3317198 "2024-11-02T17:35:24Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![itsaqibdev228](https://sea1.discourse-cdn.com/flex015/user_avatar/community.thunkable.com/itsaqibdev228/32/174512_2.png) [@itsaqibdev228](https://community.thunkable.com/u/itsaqibdev228)\ **Post date:** [November 2, 2024, 5:35pm UTC](https://community.thunkable.com/t/unexpected-application-error/3317198/1 "2024-11-02T17:35:24Z")
![image](https://us1.discourse-cdn.com/flex015/uploads/thunkable/original/3X/8/8/88f26455ff6ef0ddf19b0872cce559f5e2789fd6.png) I have worked on my app for 3-4days to complete it and suddenly this thing happened I don’t know what to do. I am unable to access to **BLOCK Section** and **Database Section** in My project HERE is the Error : ```auto Unexpected Application Error! Cannot read properties of null (reading 'type') TypeError: Cannot read properties of null (reading 'type') at https://x.thunkable.com/assets/index-CnOhYXYe.js:2422:117288 at Array.filter () at ip.generateDataSourceToolbox (https://x.thunkable.com/assets/index-CnOhYXYe.js:2422:117247) at ip.render (https://x.thunkable.com/assets/index-CnOhYXYe.js:2422:117969) at jj (https://x.thunkable.com/assets/index-kdzP9SQT.js:41:6833) at hj (https://x.thunkable.com/assets/index-kdzP9SQT.js:41:6599) at Vk (https://x.thunkable.com/assets/index-kdzP9SQT.js:41:49562) at Uk (https://x.thunkable.com/assets/index-kdzP9SQT.js:41:43849) at Tk (https://x.thunkable.com/assets/index-kdzP9SQT.js:41:43772) at Ik (https://x.thunkable.com/assets/index-kdzP9SQT.js:41:43612) ``` ---
**Author:** ![afje2x3zj](https://avatars.discourse-cdn.com/v4/letter/a/7c8e57/32.png) [@afje2x3zj](https://community.thunkable.com/u/afje2x3zj)\ **Post date:** [November 2, 2024, 9:23pm UTC](https://community.thunkable.com/t/unexpected-application-error/3317198/2 "2024-11-02T21:23:15Z")
Hi, i had the exact same problem yesterday and contacted support. I am not sure how the fault happened, but the solution was to reconnect my database (in my case google sheets). After removing the databases from the app and adding them again, i was able to access blocks again. Not saying this is the as your problem, but it solved it for me. I had to connect a lot of things again in blocks though, which took hours! Good luck, hope you find a solution! Regards ---
**Author:** ![saqibbalochabc228r5q](https://avatars.discourse-cdn.com/v4/letter/s/bb73d2/32.png) [@saqibbalochabc228r5q](https://community.thunkable.com/u/saqibbalochabc228r5q)\ **Post date:** [November 2, 2024, 9:35pm UTC](https://community.thunkable.com/t/unexpected-application-error/3317198/3 "2024-11-02T21:35:50Z")
How to disconnect when they are not allowing me to open database where all the spreadsheet and offline based sheets are. Is there is any way from google docs i can do that ? Blocks and Data section cause that error ---
**Author:** ![matt\_conroy](https://sea1.discourse-cdn.com/flex015/user_avatar/community.thunkable.com/matt_conroy/32/150843_2.png) [@matt\_conroy](https://community.thunkable.com/u/matt_conroy)\ **Post date:** [November 4, 2024, 2:54pm UTC](https://community.thunkable.com/t/unexpected-application-error/3317198/4 "2024-11-04T14:54:03Z")
@saqibbalochabc228r5q If the issue happened after needing to reconnect a database, you will want to remove the data sources previously added in Data Sources tab on [x.thunkable.com](http://x.thunkable.com) ![Screenshot 2024-11-04 at 9.51.47 AM](https://us1.discourse-cdn.com/flex015/uploads/thunkable/original/3X/2/e/2e73a69ab37f5dda43efd0ec9e65e56f44e7937a.png) You can do this by clicking on the trash can icon next to each data source. Once you do this, you should be able to go back into your project and not get the Application error. You can then [re-add the data source](https://docs.thunkable.com/getting-started/data-sources#connect-your-app-to-a-data-source). ---
**Author:** ![itsaqibdev228](https://sea1.discourse-cdn.com/flex015/user_avatar/community.thunkable.com/itsaqibdev228/32/174512_2.png) [@itsaqibdev228](https://community.thunkable.com/u/itsaqibdev228)\ **Post date:** [November 4, 2024, 4:57pm UTC](https://community.thunkable.com/t/unexpected-application-error/3317198/5 "2024-11-04T16:57:22Z")
Already fixed but thanks for your help. ---
**Author:** ![matt\_conroy](https://sea1.discourse-cdn.com/flex015/user_avatar/community.thunkable.com/matt_conroy/32/150843_2.png) [@matt\_conroy](https://community.thunkable.com/u/matt_conroy)\ **Post date:** [November 4, 2024, 4:58pm UTC](https://community.thunkable.com/t/unexpected-application-error/3317198/6 "2024-11-04T16:58:14Z")
What did you do to fix it? This may be beneficial for others to know. ---
**Author:** ![itsaqibdev228](https://sea1.discourse-cdn.com/flex015/user_avatar/community.thunkable.com/itsaqibdev228/32/174512_2.png) [@itsaqibdev228](https://community.thunkable.com/u/itsaqibdev228)\ **Post date:** [November 8, 2024, 6:51pm UTC](https://community.thunkable.com/t/unexpected-application-error/3317198/7 "2024-11-08T18:51:03Z")
Don’t worry i did the same like removing the error spreadsheets and then reimport to fix the issue. But take alot of time to reimport and reblock each things