pacita - It seems as those the filter can be rather finnicky when it comes to allowing a response to be posted,
I once tried over and over again, but it kept telling me my post wasn't valid
turns out, I used too many dots ...................... and I discovered the system reads those dots as a word - a word with too many characters (there are character limitations for words)! Once I deleted a few "dots" - the response posted!
lots of little quirks here - my answer box is still jumpy when i type more than can fit in the initial box, but I just accept this as an ongoing, annoying, but unfixable glitch with trulia.... more