Plugin Causing Error With WordPress

I can’t post a screenshot but I had to deactivate the plugin because at the top i got 2 error messages. (notices)

first is Notice: Undefined index: usercheckin_id in /home/expresselectricnc/public_html/wp-content/plugins/nearby-now/main.php on line 31

second is Notice: Notice: Undefined index: css in /home/expresselectricnc/public_html/wp-content/plugins/nearby-now/main.php on line 32

I have not changed anything on my end. This error just came out of nowhere.

Can you please help advise what may be causing this issue? With the plugin disabled none of our reviews are showing and the shortcode is still showing on the site. but dont want to have to remove it from all the pages.

I’m using the latest WordPress version 5.1.1

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