Thank you for your question.
You can create a new project for a correct Organization.
Another way to change an Org is to specify the necessary credentials in the project Properties. You can find this in the context menu of your TWS project in the Solution Explorer. Please force the pull process from Salesforce after this to get proper files. In this case, the credentials will be saved instead of OAuth connection.
One more case to solve your issue is to wait till your OAuth credentials will be expired. This time depends on the Organization settings. After this, you will get the appropriate message and then you will have an ability to change your OAuth credentials. The pull from Salesforce is necessary for your TWS project in this case also.
If you have additional questions, please contact me. I will be happy to answer them.