I replaced mine 5 years ago in Malaysia
very cheaply by taking the old ones in to a mirror shop.
They need to be done again.
In the photo
below you can see the edges are peeling.
I though I was told its important to have air space behind them and my clips allow this. But it doesn't seem to have worked.
I would ask about a coating you or they could put over the silver and ensure the edge is sealed.
It was a great enhancement to get nice new mirrors.
Sent from a stupid phone
that replaces words with weird stuff.