PHP Fatal error: Uncaught TypeError: round(): Argument #1 ($num) must be of type int|float

[blynge]

[20-Mar-2023 21:41:02 America/Nuuk] PHP Fatal error: Uncaught TypeError: round(): Argument #1 ($num) must be of type int|float, string given in /etc/inc/util.inc:2146
Stack trace:
#0 /etc/inc/util.inc(2146): round('', 2)
#1 /usr/local/pfSense/include/www/bandwidth_by_ip.inc(169): format_number('', 2)
#2 /usr/local/www/bandwidth_by_ip.php(36): printBandwidth('lan', 'local', 'in', 'hostname', 'iftop')
#3 {main}
thrown in /etc/inc/util.inc on line 2146