One of our field reps is getting an error message when she tries to add new a new contact to an account on the Salesforce mobile app. It is not a duplicate contact or account. Any idea how to fix? Thanks in advance.

duplicate value found: Territory__c duplicates value on record with id: 

Hoping to get some assistance with a simple order form I created via custom objects. However the form has some options that Salesforce Support mentioned needs to be done via Visualforce pages.  Unfortunately I don't have any experience with visualforce/coding/dev.  In a nutshell:
1. I created a business card order form for internal use
2. There are 3 options within the form and where I need some help: 1. new employee (they would fill out the entire form - I would like to only reveal full form once this option is clicked), 2. re-order - no changes and 3. re-order with changes (they would only fill out a small applicable section- would like for the rest of the form to be hidden when they click either of these 2 options) 






I sincerely appreciate any suggestions/help in advance.