Not certain I have the right dock PSU for my Dell Venue 11 Pro

I purchased a used but excellent condition Dell Venue 11 Pro, model 7140 about a year ago and got an excellent deal. I got the dock, both keyboards, protector case, all in original boxes and I'd almost swear the thing had never been used. The only issue was that it didn't come with either the tablet or the dock's PSUs. I sourced them online and have had no issue at all with the tablet PSU, but I've recently started using the dock much more and I'm having issues with its PSU. It's almost as if the connector won't go in the power port far enough. I have to really push hard and fiddle with it a lot to get it to stay seated and the dock powered. It works well power-wise, assuming I can get it to stay in and powered up, but it makes me wonder if I should be looking for another PSU model. I can't find the actual original model listed anywhere, so I can't search for the exact one that came with it. Does anyone know which PSU/Adapter I need for a Dell K10A tablet dock?

Thanks.