Reproduction

Using Barricade 3.0.0-alpha.5+1.21.5 and Continuity 3.0.1-test.4+1.21.5 with the connected textures resource pack enabled, this happens to barriers:

Here's what they're supposed to look like:

Logs

With Continuity
Without Continuity

You have a quite a few other mods installed. Test with only Continuity and Barricade and their required dependencies.

If that does not produce a different effect, try the following:

1. With only Barricade and its dependencies installed, and only the default resource packs enabled before/during game start-up, enter a world.
2. Ensure the barrier looks correct.
3. Apply a resource pack that changes texture sizes and/or adds new textures, like Faithful x64.

Reproduced without Continuity. Reload your models on every resource reload instead of only on game load.