YouTube user knowledge needed

Anyone know what this means on YouTube, and if it actually posted? (My sister is hoping NOT) She copied a comment she was working in in our computer Notebook. It was on her phone with small screen. When she copied and pasted it on YouTube, she had also accidentally copied many other comments and convos that she had saved and edited with very personal, random notes on it..that she would not want people on YouTube to see. When posting the main comment (not realizing all the other comments were above it on YouTube) it said, "Request contains an invalid argument" ...Then it looked like it never posted. Does this phrase mean it didn't post? Shes HOPING. Anyone know what the phrase means?