Journal changed the ordering of the authors. What to do now? I am facing a very difficult situation. I sent a paper for peer-review in a SCOPUS indexed journal. My supervisor though did not contribute anything rather than reading my draft insisted that I put his name in the manuscript. I had put his name as the second author as otherwise he would stop my funding. Now my paper has been  accepted and published online. To my ignorance the journal has re-arranged the author names in alphabetical order making the name of my advisor to appear first.
In our university, it is mandatory for authors to be listed in the order of their contribution. Also it was me who did all the hard work. My advisor had no idea about the reviews sent by the reviewer.
Though I had clearly made myself the first author and my advisor as the second author in the TeX file I had submitted for publication, the journal has changed it.
The journal did not send me the page-proof before publishing it online. They just changed the author ordering in the TeX file I had sent and published it as it is.
They put my paper in &quot;RECENTLY ACCEPTED&quot; section with no DOI and no VOLUME NUMBER but it is posted online and is accessible.
What shall I do now? I mailed the journal. They are not replying, it's 2 days already.
Can someone please help. Shall I withdraw the paper from the journal?
You seem to be in a Math department, and are having a problem that is going to effect everyone in that department.  I suggest you speak to the chair of the department.
There are journals in mathematics, good ones, that insist on an alphabetical order of authors.  This is also the standard in most of pure mathematics.  If you have your facts correct, your university has policy that will make it very hard for anyone in pure mathematics to publish.  Applied math is a bit different but this still will be a problem.
As an example, the journal Results in Mathematics explicitly requires alphabetical author order.