iTunes Music Library will not stay checked

I have had problems with the new iTunes, iTunes Music Library and iTunes Match since 12.2 was launched.

I have over 25000 songs. When I check the iTunes Music Library box in Preferences, iTunes connects with iTunes Store and then tells me I have over 25000 songs but when I go back into Preferences the box is not checked:

This box does not remain checked. Anyone else had this problem or a solution?

I have subscribed to iTunes Match for three years and it has worked smoothly until the update to iTunes. Now most of my songs do not appear on my iPhones or iPads. I'm really frustrated by how poorly this update has gone - what was working, no longer works. Hope that there is a fix coming soon.