Hi Tony
Welcome
I assume you are referring to a puwer pack thats in the middle of a cable bet6ween wall outlet and monitor ?
Its most likely the PSU, they fail very regularly.... can you beg/borrow a loaner to confirm that ?
they are repairable ... with a lot of effort, slicing the plastic box open etc
much easier just to buy a replacement .... most output 12VDC at ~ 4 - 5Amps
have a look on the label to confirm and then buy one of eBay, amazon etc
Dave