SSL certificate problem – any help appreciated

Hi Everyone,

Started getting the following message and not on the short codes work
CURL error: “SSL certificate problem: unable to get local issuer certificate”

Wondering whether this is to do with hosting or flickr itself. Neither version of Flickr Justified Gallery is working (3.3.2-3.3.3)

Any help is appreciated.

https://www.ads-software.com/plugins/flickr-justified-gallery/