This is a known issue right now. Some PDIs are randomly going offline for backend maintenance, and the PDI team hasn’t provided an ETA yet.

Your instance will be back up once the maintenance is completed, so if you have no urgent work, please wait for it to come online.

PDIs run on shared, temporary infrastructure, so they shouldn’t be treated as permanent. As a good practice, regularly push your scoped applications to a remote Git repository using Studio Source Control, so you can provision a new PDI and restore your code quickly if this happens again.
regards :www.linkedin.com/in/guna-sai-r-165215350