OPENCART 1.5.5.1 based web is not working - soft 404 error / or something else

Dear freelancers, some cca 14 days ago, frontpage of our opencart disappeared - there is only white blank page that doesn´t seems to be working, like there were any php code existed/executed (you can check yourself: [login to view URL]). Only several pages are working (like contacts, etc., but not homepage, or products). Admin page is OK. We or our hosting provider didn´t made any changes, all was working normally. It is probably only some very small error, simple for some expert, could someone help us to resolve this issue? On error protocols there was only this recurring error, but it seems that error was there long time ago and it didn´t affected the website, but maybe, it is somehow related, you decide) - 2019-10-13 8:24:32 - PHP Notice: Error: Tablespace for table '`optimosk_newdb`.`oc_subscribe`' exists. Please DISCARD the tablespace before IMPORT.<br />Error No: 1813<br />CREATE TABLE IF NOT EXISTS `oc_subscribe` ( `id` int(10) unsigned NOT NULL AUTO_INCREMENT, `store_id` int(11) NOT NULL, `email_id` varchar(225) NOT NULL, `name` varchar(225) NOT NULL, `option1` varchar(225) NOT NULL, `option2` varchar(225) NOT NULL, `option3` varchar(225) NOT NULL, `option4` varchar(225) NOT NULL, `option5` varchar(225) NOT NULL, `option6` varchar(225) NOT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC; in /home/optimosk/public_html/system/database/[login to view URL] on line 53