When we import product through any plugin or magento migration tool it migrates url rewrite table as well and on url rewrite when we may have any url path ” (Blank) in few entries

We just need to clear those entries from database

DELETE FROM `url_rewrite` WHERE request_path='';

And arrange setup:upgrade and clean cache after that homepage will work

php bin/magento indexer:reindex
php bin/magento setup:upgrade
php bin/magento cache:clean
php bin/magento cache:flush