My outside unite doesn't switch on but the inside one does, it had a problem of icing and they checked the inside board, but bringing it back was fault , what's the problem

Nothing about this makes any sense

Not much info with question. Sounds like you should have a tech look at this problem for you. Icing can be caused by a number of issues.. the location of the icing would narrow down the issue. Which ever the issue this would likely require a certified tech to fix.