The review results for my journal paper submitted to the special issue of a reputed journal is 45 days overdue. Is it normal and what should I do? I submitted a research paper to a special issue of a reputed computer science journal (SCI indexed) and the results were due on January 31st. However, the results have not been announced to date, and my email to the Guest Editor requesting for information on the delay has gone unanswered. I am really worried about this delay without notification, as the whole point of submitting to a special issue was to get reviews faster than regular issues. Is this big delay normal? Should I be worried that my paper is lost or worse? I can see the status "Reviewing" when I log into the journal's tracking service. Please advise on what I should do. 

Thanks in advance.
Oftentimes, and that's valid esp. for academia, a call will be better than an email. It's really easy to oversee (deliberate or not) an email, but if you call, the editor (or a secretary) has to answer. And if you have someone on the line you can ask your questions directly and he has to answer or give you sme other sort of feedback. 

It's annoying for a lot of us, since an email is easier, faster,  you can better oversee what you're writing and you don't have to call someone and speak to him personally. But from an efficency point of view, a call is in most of the cases the best approach. 

Just ask polite, don't make some sort of accusation or preasure somthing, but that are the same rules that apply for emails.