Nmap scan result: All 1000 ports filtered (HTB machine)

I'm at the starting point of HackTheBox, which tells me to run a scan by Nmap. In the instructions provided by HackThe Box itself, it doesn't seem to be so complicated since it's the starting point tutorial. I do exactly as what I'm told to do:

ports=$(nmap -p- --min-rate=1000 -T4 10.10.10.27 | grep ^[0-9] | cut -d '/' -f 1 | tr '\n' ',' | sed s/,$//)
 nmap -PN -sC -sV -p$ports 10.10.10.27 

And the result tells me that all 1000 ports are filtered. Whereas no such thing is mentioned or viewed in the tutorial and I think I'm not really supposed to face this problem. Any solutions or tips will be appreciated. I've searched a lot about this on the internet, telling me that the problem is caused because the firewall is on, and stuff like that, but there were no solutions with which I would be able to fix the problem.