Duplicate Campaign Parameters utm_term
The best fix is prevention: bring together everyone involved, establish a best practice, and stick to it. This is the best solution because it gives team members the opportunity to share and learn from one another, and potentially collaborate more effectively.
If that’s not possible, or the problem persists, Google Analytics has a handy lowercase filter built in that can solve the problem. This works great for normalizing some fields, like Source and Medium, but can cause problems with the Campaign, Term, or Content fields, which might be used by AdWords or other case-sensitive integrations. I would recommend against lowercasing any of those fields.
To create a lowercase filter, visit the Filters section of the Admin panel (we recommend setting this up at the Account level for easier use), add a New Filter, select Advanced, then Lowercase, and then the field you wish to lowercase, like Campaign Source.