Minmi

I have not worked for my previous employer for a couple of years, however when they were recently sold I had shares which were cashed in (this has put me in the wrong tax code, but this query is not about that). Subsequent to the sale, a letter was sent to my previous employer which was addressed to me. My previous employer posted it to my home address a month ago (as I don't work there anymore), but I haven't received it and don't know what was on it. Is there any way of getting a copy of this letter sent to me directly? Or is there a digital copy I can have access to? I am concerned that there is important information that I am missing.