I had my first dealing with FNBO customer service and I was, well, a bit underwhelmed but certainly not enough to take my business (and my 100,000+ AGR points and climbing) elsewhere in a huff. The issue was that my card was declined for a large, though legit, online transaction of about $1,000. (The text alert asking me if the charge was valid, Y or N, came a good 60 minutes after the attempt and was therefore useless. By then I had bought the item using another card. Losing out on the associated Amtrak points.)
Then, oddly, for the next week, my card was declined for several trivial transactions. At CVS and the transit fare machine. It was accepted for other equally trivial purchases so I was darned if I could figure a pattern. I have hearing loss so that I prefer to handle such queries by chat, not phone. (Also, a chat generates a transcript; a phone call doesn't.) FNBO disguises its chat button very well, and even when you find it, there's no mention of its days and hours. If you try it on (e.g.) Sunday evening like I did, it's unavailable, and you don't know whether it's monitored during business hours or...never. Anyway, I did try again on Monday morning and got a satisfactory resolution. But the whole saga was my first seriously sour note with FNBO.