archlinux pacman出现一些问题，error如下，求解

[hanzeil@hanzeil Linux]$ sudo pacman -Syu
error: GPGME error: No data
error: GPGME error: No data
error: GPGME error: No data
:: Synchronizing package databases...
core is up to date 0.0 B 0.00B/s 00:00 [---------------------------------------------------] 0%
extra is up to date 0.0 B 0.00B/s 00:00 [---------------------------------------------------] 0%
community is up to date
multilib is up to date 0.0 B 0.00B/s 00:00 [---------------------------------------------------] 0%
error: database 'core' is not valid (invalid or corrupted database (PGP signature))
error: database 'extra' is not valid (invalid or corrupted database (PGP signature))
error: database 'multilib' is not valid (invalid or corrupted database (PGP signature))
真心求解阿