I recently upgraded my Lumia 640 to win10 (wish I hadn't!). On 8.1 I had imported a number of ringtones some of which I used as phone tones and some for texts. Most, but not all, appeared on the list of tones when I upgraded. On advice, I deleted them all and imported them again by a usb from my pc after having checked they were all mp3 (they were) and that they played ok on the pc (they did).
It seems to have set one of my own tones as the default sms tone. Well that is fine, it's the same as on the 8.1. But, I cannot customise certain contacts to have their own sms tone. It's a bit important to me in my little world that I can do this.
I can see where I have to change the tone when I go to the contact and attempt to edit it, and select the one I want, but the little icon to save it is grey and so it doesn't seem to work, and sure enough it doesn't. Still the default, for everyone. I have changed certain people's phone ringtones in the same way and they have saved properly, but not the sms tones. Looking forward to an easy fix from somebody many thanks.
NB: That's my first question here.