here is a complete log file

[17-Jul-2017 09:57:47 UTC] Request URI: /ajax.php?act=DPU_Ajax&method=dpu_update, IP address: 192.168.200.28
#1 header() called at [/home/*****/public_html/includes/classes/dynamic_price_updater.php:463]
#2 DPU->dumpOutput() called at [/home/yabba1/public_html/includes/classes/dynamic_price_updater.php:68]
#3 DPU->getDetails() called at [/home/yabba1/public_html/includes/classes/ajax/zcDPU_Ajax.php:15]
#4 zcDPU_Ajax->dpu_update()
#5 call_user_func() called at [/home/yabba1/public_html/ajax.php:72]

[17-Jul-2017 09:57:47 UTC] PHP Warning: Cannot modify header information - headers already sent by (output started at /home/******/public_html/includes/classes/ajax/zcDPU_Ajax.php:1) in /home/yabba1/public_html/includes/classes/dynamic_price_updater.php on line 463

Any help will be appreciated