I finshed the quest at level 29. Kent is alive and willing to help. I'm now level 47 and no upgrades. I think that there might be a bug at work here, seeing as other people have no problems. Thanks for reading and I hope I'm not the only one getting this. BTW this is on Xbox one and the armour had 47 DR when I got it

It was mentioned on an Armour thread that you supposedly need to visit Kent at precisely the right level breaks (25, 35, 45) in order for him to offer the upgrades.

I haven't found that to be the case - I got my first upgrade as soon as I finished the quest, then got the second at level 38 - but clearly there are issues that some people are finding with this. Hopefully it'll be patched soon enough, or else someone will mod a fix for it.

Apparently, the upgrades are currently bugged, and you have to go to Goodneighbor exactly at levels 25, 35, and 45. Also, the quest giver says he'll let you know by radio when he's got upgrades, so you may need to actually turn on the Silver Shroud radio and hear his call before he'll give you the upgrades. I can't personally confirm either of these, but I did make sure to go to Goodneighbor at exactly level 25, and turned on the radio before I attempted to get the next upgrade, so I had no issues getting the upgrade; not surprising, since I made sure to sidestep both issues that might prevent me from getting upgrades.

I hear his radio message telling me to go to the memory den but he is nowhere to be found i even go back and check the hospital but still nothing.

Kent is usually in his room off to the side in the Memory Den with his radio.

Lucky i went at 45 by accident. I was wondering what happened to my 35, but i also recently got far enough in the RR missions that it doesn't matter.