I have submitted a manuscript in (nature) Scientific report journal. it was under review for a month. After that it is showing decision started since last 30 days? what can be the reasons for such a long time in making decision? Should I ask for a status of manuscript?
The straight forward answer is NO. This is because of the following reasons:
the journal you are talking about is highly reputed and the editorial office know their responsibility well.
30 days is very less given few situations where two or more Editors taking final decision. So it includes communication times.
although you have adrenaline rush to see the review results. It is better to wait to show that you are not desperate. (I understand it is difficult)
instead of mailing them better start working on what possible comments the work might have got. So that you can finish the revision soon, if Incase
Last, good luck!
A month is not a considerable time for review and final decision for reputable journals. You should also consider the amount of time the journal editor needs for gathering all comments and final decision. But I believe it does not hurt to drop them an Email and ask them about the status of your paper.