Neatline update error - 2.6.4 - Timeline API

After upgrading to Neatline ver. 2.6.4 in Omeka Classic, I received the following error message:

Deprecated: Required parameter $text follows optional parameter $exhibit in /home/stepping/public_html/unnatural/plugins/Neatline/helpers/Views.php on line 115

It also has an added pop-up error stating the following:
Error: Failed to derive URL prefix for Timeline API code files