This is what I see in the general setting.  

Omg,
then generalize to "survey settings".
 

Have a look in the other categories of Survey Settings, just as Joffm says. I would have to open my LS installation as well and search. Probably it is in "Text Elements" or something.

It was in the presentation,
Many thanks

Can you please let me know what is the difference between inherit(off) and off?

"inherit" means that the setting will be taken from somewhere else, e.g. general settings, etc. And the "off" signals that the general setting is set to "off". So at the moment both would lead to the same result. However, if you change the setting it is inheriting from, then this can change. So while "off" will always be off as long as you do not change the setting at this location, "inherit (off)" can be impacted by settings elsewhere.

E.g. in your screenshot there is a setting "Inherit (Group by Group)". So probably in the general settings for surveys in general of your installation the default is set to "Group by Group" mode and your survey inherits this setting.

If one day someone in the general settings of the installation changes this setting to "question by question" it will also be applied to this survey. If you check just "group by group" this setting will not be impacted by the changes in the general configuration of your platform.

I turned it to off for "Automatically load end URL when survey complete".

while before that was on inherit(off). So it should be fine, am I right?

I talked with my panel provider, and they are saying they have a problem with complete link. They said:"The link is here, but it doesn’t send me to it automatically". I attached the screenshot.  
Could this related to be "Automatically load end URL when survey complete"? It is now off, but shouldn't be on in this case because it needs to back to the panel provider?   

sahra4500 wrote:

Could this related to be "Automatically load end URL when survey complete"? It is now off, but shouldn't be on in this case because it needs to back to the panel provider?   

Yes : set it to ON

Setting it to "Off" was for checking if the link is correct. Because if it redirects you can't see if the link is correct. Once you have made sure the link is correct, set the automatic redirect to "on" and it should redirect automatically.