Hi @fabriciobarros10,
If a vendor login through the WooCommerce My Account page, they will redirect to the Vendor Dashboard by default.
If you are getting a different behavior, there must have a conflict on your site. In that case, you can run a conflict test on your site.
To run a conflict test, you can disable all plugins except Dokan & WooCommerce; also, you can switch to a default theme like Twenty Twenty, Twenty Seventeen, Twenty Twelve to find out the conflict.
However, if you want to force vendors instead of finding a conflict, you can write your own code using below given filter hooks:
For WordPress Admin Login form: login_redirect
For WooCommerce Login Form: woocommerce_login_redirect
Thanks!