attempt to yield across metamethod/C-call boundary workaround?

Hello helpers! I am working on a Object Oriented Trello API at the moment. However, I stumbled upon a huge obstacle, which might make it impossible, however, I am not sure.

Basically, I have a metatable with the .__index metamethod in it. It allows me to "read" properties from Trello objects. Such as Board.Name, etc. However, there is an error.

attempt to yield across metamethod/C-call boundary

It happens when I try to HTTP GET from the metamethod, is there a way to work around this limitation?

Edit: Apparently I need to include the code, even though I stated exactly what I was doing, so here it is:

This is a modulescript, which in this case is the Board constructor:

local HTTP = game:GetService("HttpService")
local keys = require(script.Parent.Parent.keys)

local Board = {}

function Board:GetObject(id)
    local NewBoard = {}
    local Meta = {}
    Meta.__index = function(_, index)
        local Properties = {}

        Properties["Id"] = function()
            return id
        end

        Properties["Name"] = function()

            local Ret = HTTP:GetAsync("https://api.trello.com/1/boards/"..id..keys)
            return (HTTP:JSONDecode(Ret).name)
        end

        if Properties[index] then
            return Properties[index]()
        else
            error(index.." is not a valid member of Board.")
        end
    end
    setmetatable(NewBoard,Meta)

    return NewBoard
end

return Board

Also, I am aware I should pcall() my HTTP functions, but this is a test code, it is intended for testing only, and won't be the final product.