Problem with reset link URL when using query params

Hello,
we’re using the plugin on a customer website which makes use of query parameters for defining the page language (e.g. https://www.company.com?lang=en).
When a user now requests a password reset email the link in the e-mail is generated like this: https://www.company.com?lang=fr?somresetpass=true&somfrp_action=rp&key….. which leads to an error (user is not able to reset his password).

As far as I can see one would have to fix this by changing the part where this URL is generated (in somfrp-functions.php around line 354).
$reset_url = esc_url_raw( som_get_lost_password_url() . "?somresetpass=true&somfrp_action=rp&key=$key&login=" . rawurlencode( $user_login ) );
It should check if the som_get_lost_password_url() function gives you an URL with an ? inside or not. If so there should be a & before somresetpass=true&somfrp_action=rp

Thanks and best regards,
Lukas