As SCImago is only updated once a year and Scopus is a dynamic database, it can result in inconsistencies between the metadata shown in Scopus and those available in SCImago. However, as all the metadata (i.e., country, publisher, coverage, etc.) have been provided by Scopus /Elsevier, SCImago doesn´t have the authority over these data which are property of Scopus. In this case, you need to contact the Scopus Support team to enable the changes required.