Getting references after a company closes - first time posting

I worry a reference will only confirm dates of employment. This is my first time dealing with any of this. I have one former client who liked my work. Who did you use?

Ask former colleagues and supervisors in a short message and give them a summary of the job you are applying for.

Thanks for writing this out. I went through something close to it 11 months ago, and it got easier once I kept a simple log of every call and form.