Изменить версию php до последней

Корректно установить последнюю версию PHP, чтобы все скрипты сайта отрабатывали нормально. После самостоятельной установки получили следующее:
[TypeError]
call_user_func_array(): Argument #1 ($callback) must be a valid callback, non-static method Nextype\Magnet\CProductEvents::OnGetOptimalPriceHandler() cannot be called statically (0)
/home/c/ci05692/public_html/bitrix/modules/main/classes/general/module.php:480
#0: ExecuteModuleEventEx(array, array)
/home/c/ci05692/public_html/bitrix/modules/catalog/general/product.php:951
#1: CAllCatalogProduct::GetOptimalPrice(integer, integer, array, string, array, string, array)
/home/c/ci05692/public_html/bitrix/components/bitrix/catalog.element/class.php:145
#2: CatalogElementComponent->initAdditionalCacheKeys(array)
/home/c/ci05692/public_html/bitrix/modules/iblock/lib/component/element.php:789
#3: Bitrix\Iblock\Component\Element->getCacheKeys()
/home/c/ci05692/public_html/bitrix/modules/iblock/lib/component/base.php:4061
#4: Bitrix\Iblock\Component\Base->initResultCache()
/home/c/ci05692/public_html/bitrix/modules/iblock/lib/component/base.php:4629
#5: Bitrix\Iblock\Component\Base->loadData()
/home/c/ci05692/public_html/bitrix/modules/iblock/lib/component/base.php:4609
#6: Bitrix\Iblock\Component\Base->initialLoadAction()
/home/c/ci05692/public_html/bitrix/modules/iblock/lib/component/element.php:272
#7: Bitrix\Iblock\Component\Element->initialLoadAction()

#8: call_user_func(array)
/home/c/ci05692/public_html/bitrix/modules/iblock/lib/component/base.php:4795
#9: Bitrix\Iblock\Component\Base->doAction()
/home/c/ci05692/public_html/bitrix/modules/iblock/lib/component/base.php:4813
#10: Bitrix\Iblock\Component\Base->executeComponent()
/home/c/ci05692/public_html/bitrix/modules/main/classes/general/component.php:660
#11: CBitrixComponent->includeComponent(string, array, object, boolean)
/home/c/ci05692/public_html/bitrix/modules/main/classes/general/main.php:1062
#12: CAllMain->IncludeComponent(string, string, array, object)
/home/c/ci05692/public_html/bitrix/templates/magnet_s3/components/bitrix/catalog/main/element.php:233
#13: include(string)
/home/c/ci05692/public_html/bitrix/modules/main/classes/general/component_template.php:790
#14: CBitrixComponentTemplate->__IncludePHPTemplate(array, array, string)
/home/c/ci05692/public_html/bitrix/modules/main/classes/general/component_template.php:885
#15: CBitrixComponentTemplate->IncludeTemplate(array)
/home/c/ci05692/public_html/bitrix/modules/main/classes/general/component.php:776
#16: CBitrixComponent->showComponentTemplate()
/home/c/ci05692/public_html/bitrix/modules/main/classes/general/component.php:716
#17: CBitrixComponent->includeComponentTemplate(string)
/home/c/ci05692/public_html/bitrix/components/bitrix/catalog/component.php:171
#18: include(string)
/home/c/ci05692/public_html/bitrix/modules/main/classes/general/component.php:607
#19: CBitrixComponent->__includeComponent()
/home/c/ci05692/public_html/bitrix/modules/main/classes/general/component.php:684
#20: CBitrixComponent->includeComponent(string, array, NULL, boolean)
/home/c/ci05692/public_html/bitrix/modules/main/classes/general/main.php:1062
#21: CAllMain->IncludeComponent(string, string, array)
/home/c/ci05692/public_html/catalog/index.php:9
#22: include_once(string)
/home/c/ci05692/public_html/bitrix/modules/main/include/urlrewrite.php:184
#23: include_once(string)
/home/c/ci05692/public_html/bitrix/urlrewrite.php:2
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