WSDMatty [1] filed a orphan request for spotify [2]:

Package has been out-of-date since 8/12 and will not install without manual intervention due to mismatched keys in PKGBUILD. Issue has been reported in comments since package update on 8/10/19. Fix is simple, but maintainer has not been available to correct package. I am willing to adopt.

[1] https://aur.archlinux.org/account/WSDMatty/ [2] https://aur.archlinux.org/pkgbase/spotify/