If you are aware of citations that are not yet on Scopus site, it means that you saw it elsewhere, probably on Google Scholar. As you know, the Google Scholar is a search engine that is very inclusive and publishes every citations in any format that is somehow published. Scopus is a an indexing database, and it has criteria for inclusion, so evidently, not all citations that you see on GS will appear in Scopus too.
One of my article published in scopus indexed open access journal during 2018. I paid the 200 USD since it was mentioned that paper will be indexed in scopus. Now the paper is available on line but not indexed in scopus. The same Journal is now in 2019 removed from scopus. In our Institute weightage is give only to scopus indexed papers. I had sent a request to the editors. They are not responding. What should I do? Kindly give some suggestions.