Version 2.9.7 added a new configuration item called SecArgumentsLimit, which limits the number of items added to the ARGS collection and set the REQBODY_ERROR variable when the limit is breached. There is a software default of 1000. If you expect to have legitimate requests that exceed that limit, you will need to specify a higher limit.
1. Create a new conf file
vi /etc/httpd/conf.d/01_modsecurity.conf
2. Inside of that file, place the following values replacing the number with your limit needs
# Set the SecArgumentsLimit
SecArgumentsLimit 1000
3. Save the file and restart Apache
systemctl restart httpd