New Bath Today review: Refused to provide an itemized invoice

I purchased, and has been paid for, a walk in shower tub/to shower, all the fixtures, base, locker, doors. After installation was complete I requested, since it was not provided, an invoice with a breakdown of all items I purchased by Model # and cost for each item. This is necessary for warranty with Kohler, as I spoke to Kohler about this. Have phoned at least 10 times since the end of August 2025, emailed everyone I could find, and they refuse to provide. Was even told that "no company provide invoice that is itemized", EVERY business does, including Walmart, Lowes, Home Depot, etc... Very disappointed since I spent over $19,000. Would not recommend them. Salesman was great as were installation team, and the Kohler product is good, just the New Bath Today Billing and Customer service is terrible!