Adobe spark/ creative cloud trouble with videos

I'm doing an assignment on adobe spark/ creative cloud and i have to use videos. Sadly, my adobe spark is not working and is not alloying me to upload any form of video. It was working 2 days ago where i succesfully uploaded videos on it, so this morning I tried using the same video that i had used 2 days ago and did not work!

Does anyone know what's wrong?

Thank you