There is ghost input for roll, and yaw doesn't work at all.
Classical.
Broken cable and dirt (residue) in the contacts. For the latter at least you can increase the dead zone in the axxis control in ED until you get to repairing it.
There are tons of repair videos (Fixing Thrustmaster Hotas 4/One) for that, so I won't link one here specifically.
Here are some pictures to show what awaits you (except for buttons on the mounting plate these Hotas are identical).
The T Flight Hotas 4 is a joystick controller manufactured by Thrustmaster in 2015 that is used for specific flight simulation games. Model number 4169083 is currently supported by PC and PlayStation 4.
www.ifixit.com
The yaw control is located in the stick on top of the "bone" inside it. Most likely one of the three cables has come off.
For this it suffices to dismantle the grip (you can use sticky tape to keep the parts falling off, especially the top button plate) and solder them back on.
The roll (and pitch control) are located in the white bottom housing of the stick at 90 degrees angles of the rotating axxis.
For this you need to open the body from below.
The potentiometers you can see in this pictures, the two black thingies connected with three cables each to the white housing.
They can be easily pulled out of their sockets (do not rip off the flimsy cables), cleaned, then turned by hand through all their range of movement. Do not use oil with resin in it, it might gunk up the works later.
Please be aware that this fix probably needs repeating after some month. My Hotas 4 "behaved" for about three month after that, then the throttle kept acting up (not nice when you are trying to land a loaded T9 when due to the ghost inputs the autodocking gets switched off).