Uploading files to apache server not working. How to fix?

Question

PHP

Recently, when uploading files to the site (through the wordpress and Egea engines), the files stopped uploading. Mozilla's status bar, for example, says "sending a request to 91.***.***.***". At the same time, from mobile chrome to 3g, the download, oddly enough, is going on. Through Wi-Fi - no longer.

/var/log/apache2/error.log

[Wed Apr 26 14:11:22.107204 2017] [:error] [pid 4872] [client 91.218.113.183:56342] PHP Warning: Division by zero in /var/www/micron/wp-config.php on line 89
[Wed Apr 26 14:25:25.797119 2017] [:error] [pid 4266] [client 204.93.180.6:43209] PHP Notice: Undefined index: HTTP_HOST in /var/www/blog/system/core.php on line 2
[Wed Apr 26 14:32:43.009370 2017] [:error] [pid 4264] [client 86.62.108.193:39846] PHP Warning: Division by zero in /var/www/micron/wp-config.php on line 89