Beforehand, I would like to mention that I am a first-time modder and the mistake that I am committing is probably a rookie one, and I promise to improve from now on.
Okay now to the crash,
I discovered the issue when I tried to give myself the item, depending on how I interacted with the item I would either get a null.pointer exception: Unexpected Error (when scrolling over/holding), or null.pointer exception: Render screen(moused over the item in inventory).
Initially, I believed the problem was in the BlockItem conversion, as the block possessed all the attributes that I had envisioned, minus the item, so I placed a logger event on the bus subscriber and this came up right after the event fired:
[Client thread/DEBUG] [ne.mi.re.ObjectHolderRef/]: Unable to lookup technomagical_advancements:firstblock for public static com.Esmerald1no.technomagical_advancements.Blocks.FirstBlock com.Esmerald1no.technomagical_advancements.Blocks.ModBlocks.FIRSTBLOCK. This means the object wasn't registered. It's likely just mod options.
I believe it is most likely a problem with the naming conventions, but I have been staring at my code for so long I can't see any difference.
I have attached the event bus subscriber class; a class to ensure that the name of the block will be assigned to the instance and the class that contains the information of the block itself.
I have reviewed the post about the FAQ, on the section about the registering of classes onto the bus, but it was not helpful for me at least, so I would appreciate if the responses were not just a link to that page.