Magento - 2.2.7 City missing on checkout page address section

You need to rewrite and add the following validations to these js files:

magento/vendor/eadesignro/romcity/view/frontend/web/js/action/set-shipping-information-mixin.js:15

if (shippingCityIdValue.length) {
    shippingAddress.city = shippingCityIdValue;
}

magento/vendor/eadesignro/romcity/view/frontend/web/js/view/billing-address.js:62

Replace

if (this.isAddressSameAsShipping()) {
    newAddress.city = shippingCityIdValue;
} else if (billingAddressCity) {
    newAddress.city = billingAddressCity.text();
} else {
    newAddress.city = shippingCityIdValue;
}

with:

if (shippingCityIdValue) {
    newAddress.city = shippingCityIdValue;
}
if (!this.isAddressSameAsShipping() && billingAddressCity && billingAddressCity.text()) {
    newAddress.city = billingAddressCity.text();
}

It seems that they try to add the city from the form but the values are not present anymore when you already have an address set.

Please check this file in your theme:

Magento_Checkout/web/template/shipping-information/address-renderer/default.html

City Should be remove from there, if yes then please add below code:-

<!-- ko text: address().city --><!-- /ko -->

Then File should be look like this:-

<div class="shipping-address-item" data-bind="css: isSelected() ? 'selected-item' : 'not-selected-item'">
    <!-- ko text: address().prefix --><!-- /ko --> <!-- ko text: address().firstname --><!-- /ko -->
    <!-- ko text: address().lastname --><!-- /ko --> <!-- ko text: address().suffix --><!-- /ko --><br/>
    <!-- ko text: address().street --><!-- /ko --><br/>
    <!-- ko text: address().city --><!-- /ko -->, <!-- ko text: address().region --><!-- /ko --> <!-- ko text: address().postcode --><!-- /ko --><br/>
    <!-- ko text: getCountryName(address().countryId) --><!-- /ko --><br/>
    <!-- ko text: address().telephone --><!-- /ko --><br/>
    <!-- ko foreach: { data: address().customAttributes, as: 'element' } -->
        <!-- ko foreach: { data: Object.keys(element), as: 'attribute' } -->
            <!-- ko text: element[attribute].value --><!-- /ko -->
         <!-- /ko -->
    <!-- /ko -->
    <!-- ko if: (address().isEditable()) -->
    <button type="button"
            class="action edit-address-link"
            data-bind="click: editAddress, visible: address().isEditable()">
        <span data-bind="i18n: 'Edit'"></span>
    </button>
    <!-- /ko -->
    <button type="button" data-bind="click: selectAddress" class="action action-select-shipping-item">
        <span data-bind="i18n: 'Ship Here'"></span>
    </button>
</div>