My Dear Welcome to Healthcaremagic! I have analyzed your problem and feel that it is due to Bacterial infection called Folliculitis. You have started using Mupirocin and that is a good decision. However, applying oil will not be helpful and may rather interfere with recovery by diluting the antibiotic and creating a surface that entraps dead skin cells and increases retention of sweat,however small amount that may be. It would be better to start using an antibiotic called Linezolid in such cases which gives excellent response