No response from the system when adding a non-existing project for indexing

[unordered-set]

1. open admin http://x.x.x.x:8000/projects
2. Add a project "QmSzPQ9f4U1GERvN1AxJ28xq9B5s4M72CPvotmmv1N2bN7d"
3. nothing happens (expected to have an error message)

[mzxyz]

Thanks for reporting this issue, we will fix it soon