Error on bitrix page site

The site is all working, there is an error on one page. The backup rolled back doesnt work. Needs to be fixed

[Error]
Call to undefined method BitrixMainWebDOMComment::removeAttribute() (0)
/home/p/pharmmed//public_html/bitrix/modules/landing/lib/block.php:4503
#0: BitrixLandingBlock->setClasses(array)
/home/p/pharmmed//public_html/bitrix/modules/landing/lib/update/block.php:278
#1: BitrixLandingUpdateBlock::executeStep(array, integer, integer, array)
/home/p/pharmmed//public_html/bitrix/modules/landing/lib/block.php:2558
#2: BitrixLandingBlock->view(boolean, object)
/home/p/pharmmed//public_html/bitrix/modules/landing/lib/landing.php:1073
#3: BitrixLandingLanding->view(array)
/home/p/pharmmed//public_html/bitrix/components/bitrix/landing.pub/templates/.default/template.php:181
#4: include(string)
/home/p/pharmmed//public_html/bitrix/modules/main/classes/general/component_template.php:790
#5: CBitrixComponentTemplate->__IncludePHPTemplate(array, array, string)
/home/p/pharmmed//public_html/bitrix/modules/main/classes/general/component_template.php:885
#6: CBitrixComponentTemplate->IncludeTemplate(array)
/home/p/pharmmed//public_html/bitrix/modules/main/classes/general/component.php:775
#7: CBitrixComponent->showComponentTemplate()
/home/p/pharmmed//public_html/bitrix/modules/main/classes/general/component.php:716
#8: CBitrixComponent->includeComponentTemplate(string)
/home/p/pharmmed//public_html/bitrix/components/bitrix/landing.base/class.php:1286
#9: LandingBaseComponent->executeComponent()
/home/p/pharmmed//public_html/bitrix/components/bitrix/landing.pub/class.php:1617
#10: LandingPubComponent->executeComponent()
/home/p/pharmmed//public_html/bitrix/modules/main/classes/general/component.php:660
#11: CBitrixComponent->includeComponent(string, array, NULL, boolean)
/home/p/pharmmed//public_html/bitrix/modules/main/classes/general/main.php:1072
#12: CAllMain->IncludeComponent(string, string, array, NULL, array)
/home/p/pharmmed//public_html/index.php:14
#13: include_once(string)
/home/p/pharmmed//public_html/bitrix/modules/main/include/urlrewrite.php:160
#14: include_once(string)
/home/p/pharmmed//public_html/bitrix/urlrewrite.php:2