Upgrade Debian 9 to 10 woes

Can anyone help a relative new user, I upgraded debian 9 to 10, using the NixCraft instructions, on restarting the computer the GUI xserver or gnone did not come up as usual.
Pressing ctl,alt,7 then ctl,alt,2 brought it up as it should appear.
I carried out the upgrade from VT2

any sugesstions on where to look would be welcomed.

Thanks in advance

Are you using Nvidia or any propitiatory drivers? Any errors in X server log files located in /var/log?

Hi , sorted the problem, the computer is an Intel nuc, running dual displays, it seems that I must have the display on the DP port as the primary, all then runs fine.
Debian 9 seemed ok with them the other way.
Not sure if there is a way to configure but I can live with it this way.
Thanks for your response

Glad sorted it out and posting your solution too. FYI, at least in Gnome you can go to the Settings > Display and set default screen. Another option is mess around X server file:

Linux sysadmin blog - Linux/Unix Howtos and Tutorials - Linux bash shell scripting wiki