Issues between piefed.social and friendica.world?

Was testing around with Friendica and tried adding !fediverse@piefed.social as a contact (similar as following/subscribing) and searching some post through its direct link. However, when doing so, a few errors appears while not doing what it's supposed to. The post got pulled after a few tries but still can't follow the community, as per the attached screenshot. Is it some known issue between the two instances?