Our WordPress-made website keeps shutting down

We use WordPress to create/maintain our website, but it continues to shut down. In October we used WordPress to create and maintain our agency’s new website (YLLC.org). However, since then, we have experienced several occurrences of our site completely shutting down. Our web domain on iPower, say that there is nothing they can do on their end, since their job is simply to host the website. Occasionally there will be a message, but right now it is just a blank white screen. the URL for our blog, for example, is yllc.wordpress.com. Although we use WordPress.com for both our blog and our website, we have different usernames and passwords for them. Our site is still down, and we really need this to be fixed.

Why does our site keep shutting down and what can we do using WordPress to change the situation if iPower says they cannot fix the problem? We need to fix this problem immediately, as this is our agency’s website and information to us will not be accessible. Please email me at info[at]yllc[dot]com or reply below asap.

Thanks!