Macbook air begining 2015 stuck after change SSD

Changing a SSD for a larger one is usually pretty easy. I have done it myself via a kit OWC (macsales.com) sells. We also use cruical.com at work and buy SSDs from them. As for brands and make/model... I've always shopped price as HD/SSD are all made by about 5-6 companies and all are good and should work with any Mac that supports SATA.

You will find good instructions at ifixit.com so you know what you are in for (you may possibly need some specialized "screwdrivers." That guide will tell you.

However as you seem to be in the UK I am unsure if these places sell overseas and/or will be price competitive with a reseller in the UK.

Regardless iFixit is a great resource and will help regardless of where you get the drive.

I upgraded several Macbooks with Samsung SSDs. But they were EVO 840. Here is what I noted for myself:

1. SDD had to be plugged instead of the original HDD. Plugging in instead of DVD gives issues.
2. The connector is very hard to plug and unplug to Samsung SSDs. It is much easier with Apple HDD. So you have to press firm to plug in the SSD. To unplug, gently use a small flat screwdriver to separate the SSD from the connector. This "hard" connector could be reason why you do not see the SSD.

I doubt that installing SSD in the dock station will work if you try to put it in without that dock station. OS X knows where you plug what. You need a proper device path, which means it has to be connected properly during the installation.