Funny enough my English teacher had an issue as well. The issue arises when people use Microsoft word to type up your recommendation, and try copy and pasting it into your portal. Tell your teacher to use "wordcounter.net". I told this exactly to my teacher and the next day she emailed me that everything went smoothly. Sometimes the character count is off and such, and so it won't work. Also, if you can, ask your teacher for the error message that they get when trying to submit. But I'm pretty sure it's a word count problem. Took me about two weeks to fix, until I figured it out
Hope this helps, and if not, please send the error that your teacher gets.