It's been four years, but I placed multiple orders with them over 14 months, and had no problems. I seem to remember them sometimes being hard to get hold of by phone, but when you get through, anyone I talked to knew the product line well, and had suggestions on what might work best for my (multiple) applications. I never tried email. I would keep trying by phone. They make fabulous products.
I had the impression they were very small, perhaps as few as two guys, doing it all - engineering, research, design, sales, website, shipping, etc. I may be giving them too much credit. However, a google search says they are located inside another business, so this may be a second or third endeavor for the principals. I wouldn't worry for at least another week.
If you get truly concerned, call the Better Business Bureau in Charleston SC and ask them if they have had any complaints.
ETA: Their website says clearly (at the top) that ongoing Covid-19 measures may result in delays. I know we get tired of hearing that, and a lot of folks think Covid is over, but if it really is just a few folks it wouldn't take much of a set of circumstances to affect things.