There can be many reasons for a suspension. To find issues, the only way to find them is by reading the policies and comparing it against the website.
For example you have a gofundme on the website (not allowed)
For example, there are multiple businesses at the same exact address, generally 1 address = 1 business.
For example missing contact form on the contact page.
Here are the links that I recommend you check:
https://support.google.com/merchants/answer/6150127?hl=en
https://support.google.com/merchants/answer/6363310/follow-the-merchant-center-guidelines
https://support.google.com/merchants/answer/7052112
https://support.google.com/merchants/answer/4752265
https://support.google.com/merchants/answer/13693865