[RuntimeException] 
Could not start session because headers have already been sent. "/var/www/u1134609/data/www/xn--d1ammikbg.xn--p1ai/dostavka_miss_fruttis_murmansk/catalog/constructor/index.php":21. (0)
/var/www/u1134609/data/www/xn--d1ammikbg.xn--p1ai/bitrix/modules/main/lib/session/session.php:151
#0: Bitrix\Main\Session\Session->start()
	/var/www/u1134609/data/www/xn--d1ammikbg.xn--p1ai/bitrix/modules/main/lib/session/kernelsessionproxy.php:47
#1: Bitrix\Main\Session\KernelSessionProxy->start()
	/var/www/u1134609/data/www/xn--d1ammikbg.xn--p1ai/bitrix/modules/main/include.php:185
#2: require_once(string)
	/var/www/u1134609/data/www/xn--d1ammikbg.xn--p1ai/bitrix/modules/main/include/prolog_before.php:19
#3: require_once(string)
	/var/www/u1134609/data/www/xn--d1ammikbg.xn--p1ai/bitrix/modules/main/include/prolog.php:10
#4: require_once(string)
	/var/www/u1134609/data/www/xn--d1ammikbg.xn--p1ai/bitrix/header.php:1
#5: require(string)
	/var/www/u1134609/data/www/xn--d1ammikbg.xn--p1ai/dostavka_miss_fruttis_murmansk/catalog/constructor/index.php:23
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