Hi I checked your contact page with default Joomla template and seems email not working. I suggest you to write the issue on Joomla forum as its default Joomla contact form. There is something wrong in your Joomla contact and server email. https://forum.joomla.org
Sorry to give more information as its something that is in Joomla or from the server.
I already suggested you post an issue on Joomla forum as you have the same issue with default Joomla templates. Its default Joomla contact form and as per your reply it seems you server not supporting Joomla contacts that is strange, you should raise the question on Joomla forum as requested before.
For emails notifications please check the email you added to Joomlart account, you will get the email on registered email account only.
Joomla is Open Source platform and not belong to Joomlart. We provide template and extensions for Joomla CMS only.
If your server does not support Joomla you may look for changing the hosting that supports Joomla application.
I would be happy to assist you further but its something that is on your server side. You can post the query on Joomla forum to get more information on this.