Error 1119

Hi, I’m trying to change text of a textfield. I think I can’t locate it. Here’s my code:

container.getChildByName("beatNormal_" + boxArray*.name.substring(11, boxArray*.name.length)).alpha = 1; // This works fine
trace(container.getChildByName("beatNormal_" + boxArray*.name.substring(11, boxArray*.name.length)).txTitle.text); // This gives me error 1119