Open up the power supply.
You’ll probably find some burned up capacitors like in the attached pic.
View attachment 11177
I had 2 units fail that way. Reef Brite customer support was very poor.
I ended up buying a 24V 6A power supply through Amazon.
Also had to get a 5.5mm x 2.5mm Male Plug to 5.5mm x 2.1mm Female Jack DC Power Adapter.
It’s held up for over a couple years now.
Can you let me know which power supply you purchased on amazon?
Just search for any 24v 6a and 5 stars