I too for this morning. HELP!

I have the same strange problem, I can place one bridge, but not the other...

Can't place this[imgur.com]

This works fine[imgur.com]

update your mods on server.

After Steam has downloaded an update you need to launch ark first in order to install the mod/s. then copy files to your gameserver

Agree with Daywalker. I've had this happen many times with various mods and it's always been the result of a mod being outdated (or broken). The process to fix it is simple;

1. Run Ark on your computer (this installs the mod updates locally)
2. Stop your server.
3. OPTIONAL - Delete the mods from your server.
4. Upload the updated mods from your computer to your server.
5. Start your server.

I put step 3 as optional because it's fairly rare for overwriting the mods to not update them. That said, I do step 3 every time on my own server to prevent issues and remove any "garbage" files.

To lessen downtime, upload the mods as ZIP files (Max 900mb per Zip). Most server hosts have an "unzip" option in their file managers that can handle them. That way you only need to shut down your server long enough to delete the old mods and unzip the updated ones with the file manager.