Message may only contain numbers, letters, spaces or common symbols. what am i doing wrong please help

You are probably posting a symbol which is not allowed.

Are you typing your message or copying and pasting?

tried copying and pasting and typing keep getting that message on both

Sometimes happens to me with punctuation. You might need to take out all comma's and apostrophies and retype them.

done that still says the same thing doing my head in i cant post results and fixtures for my clan etc

Maybe it's the space which are easily confused as the No-break space character (U+00A0).

If in doubt, try pasting one paragraph (or less) at a time, editing each time to add the extra paragraphs. When the offending character(s) appear, it'll be easier to find them.