The laptop does not see the freshly purchased RAM, what could be the reason?

Question

laptops

He does not see a new RAM in any of the slots, he sees the old one in any slot. When installing only a new bar, the display does not light up after switching on (only the power indicator).
A barcode is glued under both laptop memory slots, which the scanner recognized as follows: KN4GB07035737016856600
Laptop: ACER TravelMate TMP278-M-30ZX https://www.citilink.ru/catalog/mobile/notebooks/4...
Native 4Gb RAM everything is fine :

Purchased RAM, which it does not see in any of the slots:

Here is a link to where I bought it: https://technopoint.ru/product/484c1e1dcaaf3120/op...
It was sealed in a box, obviously not used without visible mechanical damage

A barcode is glued under both memory slots of the laptop, which the scanner recognized as follows: KN4GB07035737016856600

Answer 1

In the characteristics indicated on the site - the supported memory is DDR3L (1.35V), and on the sticker on the second plate - 1.5V. The voltage is not suitable, take it at 1.35.

Answer 2

A barcode is glued under both memory slots of the laptop, which the scanner recognized as follows: KN4GB07035737016856600

That is, nothing prompted you to look at your very first photo carefully and, lo and behold, see that this is also written in numbers on the module above the barcode? But writing it twice is a must :D A
barcode is not needed for humans, to recognize the code is, to put it mildly, utter nonsense!
Old memory - low voltage. Made by order of Acer (although this is not important). And yet, it is most likely one-sided (and single-rank), and the new one is 1.5 volts - a "high" voltage, two-way (and two-rank), although the "row" only concerns the compatibility of the two at once. Here with the voltage, most likely an ambush.
Oh yes - putting delicate electronics on a woolen (and even synthetic) rug is a brilliant solution! Always do this, support the manufacturers and the subsequent chain :D

Answer 3

The rank of cans should be on the drum. But if you can't return it or don't want to sell it, there is a backup plan: Most 1.5V modules work fine from 1.35. Google - "SPD firmware". The operation is simple