To edit the position of the links in "My account" block (my Prestashop version is 1.7.5), open the modules/ps_customeraccountlinks/ps_customeraccountlinks.php
Around line 100 you will find "my_account_urls = array". In this array is set position of links with numbers from 0-5.
$my_account_urls = array(
2 => array(
'title' => $this->trans('Orders', array(), 'Admin.Global'),
'url' => $link->getPageLink('history', true),
),
3 => array(
'title' => $this->trans('Credit slips', array(), 'Modules.Customeraccountlinks.Admin'),
'url' => $link->getPageLink('order-slip', true),
),
1 => array(
'title' => $this->trans('Addresses', array(), 'Shop.Theme.Global'),
'url' => $link->getPageLink('addresses', true),
),
0 => array(
'title' => $this->trans('Personal info', array(), 'Modules.Customeraccountlinks.Admin'),
'url' => $link->getPageLink('identity', true),
),
);
if ((int)Configuration::get('PS_ORDER_RETURN')) {
$my_account_urls[4] = array(
'title' => $this->trans('Merchandise returns', array(), 'Modules.Customeraccountlinks.Admin'),
'url' => $link->getPageLink('order-follow', true),
);
}
if (CartRule::isFeatureActive()) {
$my_account_urls[5] = array(
'title' => $this->trans('Vouchers', array(), 'Shop.Theme.Customeraccount'),
'url' => $link->getPageLink('discount', true),
);
}