I'll jump in here and make a statement, although it wasn't myself who liased with you, gunuk.
I have asked for the other side of the story but I have no reason to think you're making any of this up. If what transpires is true then the response that you received was poorly worded, and while it did offer to replace the device, the language and style of writing leaves a lot to be desired. As part of my association with the EDTracker team, I can only apologise.
The USB connectors on the devices are obviously not made by us but are part of the Pro Micro design, so there is little we can do to change the way they are made other than make our own design. What we do do is beef up the solder points a little to hopefully improve the reliability of the item but, as may have said above, the USB connector does not like being waggled around and that is why we include a cover sheet with all devices with a bold "WARNING" text stating the above.
If your device did not have the solder beefed up, that is a failing on our part and we should rectify it.
If you did not have a letter included with your device, that is a failing on our part and I have reminded those who send devices out that they should include it.
If you are still willing to give us an opportunity to fix this for you, I would and will quite gladly attempt to repair your device for you and, considering the way this has been handled, will do it free of charge naturally.
Hope you don't mind me posting this out in the open but I like transparency here and I like to think that most, if not all, of our 'customers' trust us enough. This is an unfortunate bump in our otherwise blemish-free road and I'd like to nip it in the bud promptly!