Due to 2Apply being used by many Real Estate Agencies, each agency can customise their 2Apply Applications to require different information to be able to accept your application in full.
As such, if an application is asking you to complete more fields than a previous application, this is due to that Agency requesting the additional information to be able to accept your application to start processing.
If there are fields that you can not complete due to this, you will need to contact that Agency direct on how best to proceed with submitting your application.