I have a student that completed Duolingo lessons on her phone for dates ***** to...

I have a student that completed Duolingo lessons on her phone for dates ***** to ***** and none of her progress is showing up. She originally signed up on her school chromebook and completed numerous lessons on it. She started completing them on her phone and now, none of her progress for the past three weeks has shown up. I had her exit the class this morning on Chromebook and rejoin and it didn't affect the scores showing. For most students this works. I need to know that she complete all four lessons for the first level on each of these for her grade. I have been on medical leave for the past three weeks and have been assigning a daily topic. She and her mother are adamant that she has completed them at all levels, but I really need to see that and all she can show me is a crown for level *. They can test out at level * and still get a crown after only completing one or two lessons. what can we do. Grades are due at * am tomorrow *****. My name is Tanya Coffey and I am a high school Spanish teacher at Wolfe County High School. The parent is very irate with me and will be contacting my principal in the morning if we don't get this resolved. I have recommended giving her an incomplete until we get this resolved but that will not pacify her either. Please help as soon as possible. Thank you. Tanya Coffey