I ran my own interconnect in N. Hollywood, CA between 1984-1993. During the slow times I would call every customer I had and tell them I was just checking to see how they were doing, and ask how their phone system was working. Most would simply say things were running smoothly with no problems, but I would always drum up some service work while making my calls which would tide me over through the slow times. It's a good policy to check in with your customers to show your concern for their operation, and remind them that you're still in business.
Get on the phone and call those customers you haven't heard from in a while! - Brian Cox
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