There are more ways to enable this option:
1) Option can be enabled in the 'EDIT' - 'Settings' - 'Respondent access' tab:
- In the row 'Cookie', you must choose between the following options: save cookies 'until the end of browser session', 'for 1 hour', 'for 1 month'.
- This allows you to select 'Starts at the last submitted page' in the 'If user returns' line.
When you turn on the storage of cookies, the system will display a ribbon at the top of the respondents' browser screen, notifying them that the site uses cookies for optimal performance, and ask them if they agree to the use of cookies.
2) Option can be also enabled in the tab 'EDIT' - 'Settings' - 'Basic settings'. Within the Interactive elements, you check 'Yes' by the 'Display continue later option'.
This function allows the respondent to pause with answering the survey and to continue later. Respondent enters their email address, and on that email receives a message with a URL, via which can later continue with answering the survey.
3) The third option is the use of individualized invitations. In the 'PUBLISH' - 'Invitations' tab, you need to enable the 1KA system to send e-mail invitations and use identification codes, which allows the respondent to later continue with answering the survey or to later return to the beginning of the survey. More about that is available here.