
Quoting
adjusterjack
I'm guessing that you picked those names as an example of the similarity but that those aren't the actual names of either business.
Without the actual names there's no way to provide any helpful comments and revealing actual business names here is against the rules.
If, as Mr K suggests, that you aren't infringing, I suggest you have a trademark attorney review the situation and respond to the sender of the letter.
If your next comment is "I can't afford an attorney" well, the choice is pay one a little money now for the letter or pay one a lot of money later if you ignore the letter and get sued.