The disk is full — often Docker's own storage rather than your home directory
Images, stopped containers, build cache and volumes accumulate on a separate filesystem from your working files, so a full disk here can be invisible from df -h ~. Workflow work directories are the other usual culprit: they keep every intermediate file from every task.
Check where it is actually full (df -h, then docker system df). Reclaim with docker system prune — but read what it lists before confirming. For workflows, clean old work/ directories once results are published; that is usually where the bulk sits.