Update: I called Air Berlin late this morning - 10:00 a.m. EST and 4:00 p.m. Berlin time. I am not sure if my phone call was routed directly to Berlin or not, but the agent I spoke to was very professional, polite, understood EXACTLY what my problem/issue was and took care of it. My seat assignments have been restored, and I was provided what I had asked for to begin with - an e/mail confirmation from Air Berlin showing not only my flight confirmation, but my seat assignments which I had paid for months ago.

I don't know why this had to be such a hassle, but it was. I simply had requested (many times) written confirmation for something I had paid for. This was finally accomplished ......... WHEW!!

My advice to anyone who may be interested is this: be aware of the time difference between Berlin and know that if it is very late at night or very early morning hours in Berlin, your phone call may be routed thru Romania as mine was (twice), and you may be dealing with an agent who is not quite as well trained (and probably not well paid) in a "call center". In retrospect, this may seem common sense, but from my time zone it means I probably could not call during my normal work hours. I had off work today, so it was easier to accomplish! Anyway, I thought I would throw that out there as advice. Be aware of when you place your call.......

Also, these are other phone numbers I found after searching on line:
01805 737 800 - "Air Berlin Worldwide Contacts"
0049 (0)30 3434 3434

These are toll numbers, but the number that is provided on-line as toll free for Canada and the US is what I used during my first couple of attempts to contact Air Berlin, resulting in a situation that was not very pleasant and not very professional. I did NOT use either of these numbers, but was prepared to do so if I did not get my situation resolved.

I have no idea if this would have gotten me directly to customer service or not (the call center last night told me I could NOT contact customer service myself), but they are alternate phone numbers I was prepared to try if need be.