how to repair UPS?

ss 

Unless it's some no-name junk, it may just need a new battery. Test the battery with a steady load like a 12V automobile headlight, and measure the voltage. It'll probably drop from 12V with no load to 10 or 8V when a substantial load is applied.
orksecurity7 years ago
Assuming you mean Uninterruptable Power Supply: The answer depends on what's broken. Maybe the fuse blew. Maybe the battery's worn out. Maybe you managed to really destroy it.  Maybe you just forgot to plug it in (yes, it happens).

Someone who has a bit of a clue needs to look it over and define the question a bit better.
Bigev7 years ago
Write a letter complaining of slow service?

Use FedEx instead?

Corporate espionage?

Consulting services?
.  :)