Hello Atul,
I think it is a conflict in your userlibs, things to troubleshoot are the following:
1.
- download the latest version of the database connector again
- clean up your deployment directory
- rerun your application
- check if your problem persist
2. Clean up your userlibs
- go to your app directory
- navigate to userlibs or vendor libs and check if you have unused or duplicated user lib keep one of them and move the other out of the app directory
- synchronize app directory
- clean deployment directory
- rerun
- check if problem persist
3.
- create a blank app
- download the latest version of the database connector module
- run your application
- if everything works check your userlibs and vendorlibs
- compare them to your main project and see which userlib you miss or is different
4.
- try to find the user lib that you miss
- download it and added to your project
5.
- create a ticket at mendix when it is a mendix marketplace module
- otherwise contact the owner of the module
Hope this helps
Good luck!