Error: "Accessed None trying to read property FirstPersonGamemodeRef"

Hello!

I’m currently trying to make a New Game button for my game’s main menu, which is supposed to delete the current save and make a new one. However, when I press the New Game button I get this message in my Message Log:

Then when I load into the level a new save has not been made as the level looks the same as before.

This is the blueprint where the error takes place:

I also get these error messages that appear regardless of whether I start a new game or not, so I’m not sure if they’re relevant to this issue but I’ll include them anyway in case they are:

Blueprint error takes place:

If anyone has any idea what could be going wrong here, it would be great to get some pointers. Thank you!!