Hi babamal123,
From the look of the URL I'm assuming your referencing this from the DevNet Sandbox instructions on how to connect to your Sandbox.
Happy to reiterate a couple of points that work for me every time:
1. Ensure you use Cisco AnyConnect and copy and paste the URL directly into AnyConnect
2. Ensure you use the correct username and password
3. Ensure you have an active internet connection and your ISP supports VPN traffic and any security appliances allow VPN traffic as well.
If you need any further assistance then feel free to reply back detailing what steps you take to connect using that URL and what sort of error your getting back. Screenshots ect help a lot for folks like myself wanting to help out!
I hope this helps!
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