I wrote to them several times about that umbrella!! But haven’t seen it in the store yet!!!
I suspect they get a boatload of email with limited staff. Hopefully, someone will finally get one of your email and forward it to the appropriate people.
I just checked their store site - did you try this instead of the regular contact on the main site?
Please feel free to contact us at shop@donaldtrump.com with any merchandise questions or order inquiries.