ssh access error - is not in the sudoers file. This incident will be reported.?

Question

SSH

I installed Centos7.6 + Vestacp
for ssh on the server and created a new user for everyone (except the new one), including root, closed the entrance, only a new user can get through ssh, BUT, ... but I did not add the user to sudo, those. The new user has access via ssh, but he cannot execute commands .. we have the error "" is not in the sudoers file. This incident will be reported. "", for root I closed the entrance.
Can you fix the situation???
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In /etc/ssh/sshd_config

AllowUsers NEWUSER
Protocol 2
PermitRootLogin no

Answer 1

Su -
Root password

Answer 2

Console. Rooting through the console and editing all the necessary files. If for some reason the console is not available - only a permutation.
PS: The tree of knowledge grows from the bumps on the forehead.