Warning: Cannot use a scalar value as an array in C:xampphtdocsmagentovendormagentomodule-emailModelAbstractTemplate.php

I get this error ho to solve it ?

    {
        $store = $this->storeManager->getStore($storeId);
        if (!isset($variables['store'])) {
            $variables['store'] = $store;
        }
        if (!isset($variables['store']['frontend_name'])) {
            **$variables['store']['frontend_name'] = $store->getFrontendName();**
        }
        if (!isset($variables['logo_url'])) {
            $variables['logo_url'] = $this->getLogoUrl($storeId);
        }

$variables[‘store’][‘frontend_name’] = $store->getFrontendName();

error in this line if I gives any idea.