Sounds like you didn't update the game.setMapId command to the correct mod. This command is found in your map's Menu\Init.con file. Every map should have this command. The vanilla maps always have it set to BF1942. But must be changed to match the name of your custom mod if you are editing/creating a map in a new mod.
For example, this is how it looks for my Battlefield Heroes'42 mod:
The name usually matches what the name of mod folder you created. But technically it uses the name the "game.setCustomGameName" in your mod's main init.con file. Usually the folder name just happens to match. If not, then refer to what you used on that command in your mod's init.con file.
If you didn't add the command or set it to the wrong mod name (for example you edited existing vanilla maps and didn't update the Menu\Init.con file in your edited maps to use your new mod name), then it will not load any custom assets specific to the mod you ran the map in. Menu/HUD elements might still work, but anything else like custom mod assets and such used ingame won't be correct or missing entirely.