slogin displaying warnig after login

Hello sir,
I install recently slogin at my site iotaclasses.com, now I found some warnings after login at above user menu, "Warning: sprintf(): Too few arguments in /home/zqpvwbw8rlgn/public_html/iotaclasses.com/portal/libraries/src/Language/Text.php on line 321" can you please assist me why is it showing warnings? and how to resolve it?

Hello. Reduce the level of error output in the site settings.
Judging by the text of the error, it is not related to Slogin.