How is the Zakat calculated for a person who has money and a device that he bought for trade, but it developed a defect and has not yet been repaired or sold? And is this device considered among trade goods and its price added to the money to reach the threshold (nisab)?

If the device was purchased with the intention of selling and profiting, then it is considered a trade commodity, and zakat is obligatory on it upon the completion of a hawl (lunar year) from its original purchase, provided it reaches the nisab (minimum threshold) when combined with cash or other commodities. The device is valued at its current market price, whether defective or sound, and it is added to what the zakat payer owns, then zakat is paid on the total amount. If the device is repaired and its value increases, what is considered is its value at the time the hawl is completed, and the profit is subordinate to the principal.