I have wondered what the locked means as well. Under classified there is a rules posting. I know you have to have regular status which looks like you do and you can only sell 15 items each 7 days. I messed up first time I sold some items so probably a good idea to read. I think you're supposed to list them all as one posting not 10 or 15 different posting. The moderators were very nice in helping me so if you're not sure pop them a pm.