Just to elaborate more on the question. All the authors in the paper are Africans who base in Africa except the corresponding author who is also African but, based in Europe.

I have never heard of a rejection based on the authors' location. It is totally irrelevant. There is probably some misunderstanding involved or that's a strange journal.

Dear Alexander Serenko I am not aware of any misunderstanding. I have lived with this concern for long and I wanted to know if I was alone in this experience or someone have had similar experience, maybe that would help me to forget about it.

Sometimes journals reject papers for strange reasons. I suggest you contribute to other journals, or make a complaint accordingly.