Plugin not working php 8.1

Plugin does not work with php version 8.1, wordpress sends message:

An error with type E_ERROR occurred on line 851 of the file /wp-content/plugins/social-networks-auto-poster-facebook-twitter-g/inc/nxs_functions_wp.php. Error message: Uncaught TypeError: Cannot access offset of type string on string in /wp-content/plugins/social-networks-auto-poster-facebook-twitter-g/inc/nxs_functions_wp.php:851
Stack trace:
#0 /wp-content/plugins/social-networks-auto-poster-facebook-twitter-g/inc/nxs_functions_wp.php(807): nxs_showNetworksList(Array)
#1 /wp-content/plugins/social-networks-auto-poster-facebook-twitter-g/inc/nxs_class_mgmt.php(206): nxs_showNewPostForm(Array, false)
#2 /wp-admin/includes/template.php(1401): nxs_adminMgmt->metabox_newPost(NULL, Array)
#3 /wp-content/plugins/social-networks-auto-poster-facebook-twitter-g/inc/nxs_class_mgmt.php(92): do_meta_boxes(Object(WP_Screen), 'normal', NULL)
#4 /wp-content/plugins/social-networks-auto-poster-facebook-twitter-g/inc/nxs_class_mgmt.php(116): nxs_adminMgmt->showPage('SNAP: .......')
#5 /wp-includes/class-wp-hook.php(307): nxs_adminMgmt->showPage_dashboard('')
#6 /wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters('', Array)
#7 /wp-includes/plugin.php(476): WP_Hook->do_action(Array)
#8 /wp-admin/admin.php(259): do_action('snap-autoposter...')
#9 {main}
  thrown

You can help?