When this occurs, it is because not all the medication has been administered. Residual medicine on the skin is caused by the device not being placed firmly enough on the skin and/or not being placed at 90°. Press the NFIS Device firmly onto the injection site, until the skin is clearly sealed with the injection device. Hold the NFIS Device in place for 5 – 7 seconds to allow the medication to penetrate the skin completely.