Musecore won't let me write this measure

Hi I'm not sure if I'm missing something really obvious or if this is a bug. Musecore will not let me write this measure into it.
In the treble clef I have tried all sorts of ways, but musescore keeps doing it's own thing! the dotted augmentations affecting the lower notes C DE can be entered but when I try and enter the eighth note above the dotted C musescore won't let me it keeps removing the dotted notes and entering its own notes.: 3 eighth notes. To me the lower notes are played on the 1st and 4th beats, and then there is a little melody played above them. But MS wont allow me to do this. In the last chord the CDA, CD are dotted but A isn't. muscore will not allow me to remove the dot on the A and therefore I can't put in the eighth note G sharp
thanks for reading
Kwisj