Hmm. It seems that the micro sd card and the sim card are on one removable tray. Try applying a bit more pressure on the ejector key while it is in the hole. It is best to make sure the ejector key is parallel with the device and that you are not at an angle. Otherwise you may miss the tray depression lever and the tray won't come out. If that still doesn't work, try wiggling the ejector key and applying pressure. Some removable trays are a bit more stubborn than others.
If that doesn't work, you may want to try using a sewing pin. Do this as a last resort as sewing pins are longer than the sim ejecting tool and can cause unwanted damage of the pin goes to far into the phone. Again, this is a last-resort type of decision. If you don't want to do that, try bringing it to an att / verizon / tmobile store and getting someone more experienced to do it. I can't imagine they will charge you if all you are doing is inserting / ejecting a sim card tray.