Php 7.2.9 not working with Jetpack: Call to undefined function ctype_digit()

Hi all

Need some guidance here
moved my WordPress site to a new server
from 14.04 to 16.04
Php 5 to

Everything is fine
But the Jetpack plugin is not working
When click on setting and dashboard, the jetpack plugin is returning blank

This is the PHP version:
PHP Version => 7.2.9-1+ubuntu16.04.1+deb.sury.org+1

Attached is the debug log

[09-Sep-2018 02:17:01 UTC] PHP Fatal error:  Uncaught Error: Call to undefined function ctype_digit() in /var/www/html/mainsite/wp-content/plugins/jetpack/class.jetpack-signature.php:176
Stack trace:
#0 /var/www/html/mainsite/wp-content/plugins/jetpack/class.jetpack-client.php(118): Jetpack_Signature->sign_request('FV&(*OTKMHhm4Ca...', 1536459465, 'fUhF4iYD2N', '5lT4ddluf75zdF0...', 'POST', 'https://jetpack...', '<?xml version="...', false)
#1 /var/www/html/mainsite/wp-content/plugins/jetpack/class.jetpack-ixr-client.php(36): Jetpack_Client::remote_request(Array, '<?xml version="...')
#2 /var/www/html/mainsite/wp-content/plugins/jetpack/class.jetpack.php(1726): Jetpack_IXR_Client->query('wpcom.getUser')
#3 /var/www/html/mainsite/wp-content/plugins/jetpack/_inc/lib/tracks/client.php(80): Jetpack::get_connected_user_data(1)
#4 /var/www/html/mainsite/wp-content/plugins/jetpack/class.jetpack.php(4633): jetpack_tracks_get_identity(1)
#5 /var/www/html/mainsite/wp-content/plugins/jetpack/_inc/lib/admin-pages/class.jetpack-react-page.php(254): Jetpack->build_connect_url(true, 'https://launchb...', false)
#6 /var/www/html/mainsite/wp-content/plugins/jetpack/_inc/lib/admin-pages/class.jetpack-admin-page.php(117): Jetpack_React_Page->page_admin_scripts()
#7 /var/www/html/mainsite/wp-includes/class-wp-hook.php(286): Jetpack_Admin_Page->admin_scripts('')
#8 /var/www/html/mainsite/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters('', Array)
#9 /var/www/html/mainsite/wp-includes/plugin.php(453): WP_Hook->do_action(Array)
#10 /var/www/html/mainsite/wp-admin/admin-header.php(118): do_action('admin_print_scr...')
#11 /var/www/html/mainsite/wp-admin/admin.php(216): require_once('/var/www/html/m...')
#12 {main}
  thrown in /var/www/html/mainsite/wp-content/plugins/jetpack/class.jetpack-signature.php on line 176

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