can’t receive email, but can send email from hotmail account

No problem until yesterday. I just noticed I am not receiving any mails to my hotmail account. I use personal domain name for this hotmail account. I logged in hotmail website, and set my email to be forwarded to my other email account. I don't think that is working either. I use this email account for my business, and it is very important for me to get my emails promptly.