Is reimport of vegetable products to US possible during Covid-19?

Hi there,

I have a question.

Is it possible to reimport products to US?

We purchase products (vegetable products) from a supplier in US and import them to Japan,  and sell them to our customers in Japan.

One of our cutomers wants to import those products to their subsidiary company in US. In short, this is a kind of reimport. (US→JP→US) 

However, the supplier in US says Custom Border and Protection will not allow that kind of transaction in this situation (COVID-19.)

Is it true?? Can't we export the products imported from US to US?

Thank you.

Have a nice&safe day.