I can't get the SIM to click into place in the B818. I definitely have the correct size SIM, and am inserting it as shown in the instructions. I've tried to keep it down by putting the cover back over it, but it pops the cover off. Any helpful advice?
Sure you are pushing it in far enough for it to click? Some sim holders require a bit more force than others however there is always the off chance that it is damaged. If you have an Optus shop nearby it might pay to ask them to look at it for you.