iCloud does not count for this calculation. Only your regular space counts. How much space do you have left? macOS does some funny calculations and so the available space displayed in macOS is not always what is really available.
See here:
What finder displays is 131GB free. What is really free is 115GB. The rest is used but marked as "can be deleted". If your free space is less than 30-50GB, funny things start to happen. Try to stay above that value.