- Click on Materials and search for playerclip
https://ibb.co/BK8x1XL

- select the material (click on it)

- select the Block Tool (Shift+B) and create your invisible wall / barricade how you like / need it. with the player clip you can also prevent the player from teleporting to objects. However, the player clip must be high enough so that the player cannot teleport onto it. if it is too low or you manage to teleport there from another position, then you can always jump onto the player clip (you will be floating in the air then). so make sure it is not reachable from any position with the teleport and high enough.

For sure you could also use the Teleport_clip material. Then you can not teleport in the area where the material is used

thanks