I know what to do (found it out myself!) when you're about to type in a name (pokemon nickname, OT, wondercard ect) left click so now your cursor appears ready for you to write, then right click and a menu will appear, click 'show undicode character' then a colourful line will appear where you type the name, click on where you type the name again and hold backspace untill the colourful line dissapears, now enter what name you want click OK and it should stay there, Private message me if you're confused.