Hello,
I have a Joomla 3.9.25 site with DT Register 4.2.8;

We have 2 different ways to register to an event.

1) the user, not a Joomla user, fills in all the registration form fields for the event and then proceed to "pay now".

2) the user, already registered to the site as Joomla user, login to the site. So in this case, when he goes to register to the event, the registration form is already filled in with his data.
Then he proceed to "pay now".

We tested it with Paypal Standard. So when the user goes to pay he is redirected to the PayPal portal. After he complete the payment on Paypal site, he is redirected back to our site.
In case 1, we noticed that in some case, seems if the user keeps to much time to complete the procedure, when he is redirected back to the site, he is no more logged-in, the thank you page is quite empty with only the "Print this confirmation"; as result he doesn't receive confirmation email and he is not registered to the event (dtregister-fail.jpg).

Instead if the user complete the whole procedure much faster, the DT Register thank you page echoes also a notification, the user receives the confirmation email and is correctly registered to the event. (dtregister-ok.jpg)

We noticed that in DT Registered configuration, there is a parameter "Session Length"; is it related to this behaviour and if yes, when the system starts to count this timer; for example if I have a value of 180 seconds, when it starts to count the 180 seconds, when the users login, when starts to fill in the registration form, when it click on "Pay now" button, or what else?

Now considering case 2, is there any difference regarding "Session Length" in case of not logged-in user?

Kind regards,
Matt