Hi,

I have a redoran stronghold(Indarys Manor)

, built via redoran house questline. I put a lot of stuff in chests in "master bedroom" and they respawned with default content after a while is this supposed to happen? in your own stronghold?

I remember that I used to store stuff in my redoran stronghold, but with current playthrough it resets stuff.

I don't have many mods, but I do have stuff like morrowind code patch and morrowind patch project. Do they mess with this?

Normally, not a single chest in the game will ever respawn once you alter the contents in any way. (except the Guild chests, but you cannot place any items inside them anyways)
The only thing that comes to mind is if the chests change ID during construction of the stronghold. But that seems very unlikely.

The patches shouldn't change these chests in any way, although there are many versions of the Patch Project and some have bugs.

Post you load order, as this is very likely a mod problem.

Also, which exact chest is it?