If you dont want to leave your train of thoughts by leaving the desk/computer (yet):
Use the help provided by rubber duck (can also be a text editor or colleague if you prefer):
Explain everything you did so far, as you would need to in a stack overflow question or thorough bug report.
In most cases I do that, the missing piece get's obvious.
If you have the patience to write it down and it doesn't help you can of course ask that question here or somewhere else, or file that bug...
For further actions, you may consider blocking this person and/or reporting abuse
We're a place where coders share, stay up-to-date and grow their careers.
If you dont want to leave your train of thoughts by leaving the desk/computer (yet):
Use the help provided by rubber duck (can also be a text editor or colleague if you prefer):
Explain everything you did so far, as you would need to in a stack overflow question or thorough bug report.
In most cases I do that, the missing piece get's obvious.
If you have the patience to write it down and it doesn't help you can of course ask that question here or somewhere else, or file that bug...