Error in Control Tower

My process has this problem. What does it mean?
events_root_e20a60ac-e6cd-4dbf-aa53-e8dd95665794_2019-10-07.xlsx (6.0 KB)

There are no available nodes for the process to run on. Perhaps, another process was executed at this time?

Yes, sometimes the bot don’t finish the process, it’s running, when it try to start another process.