'Tis the season for title transfers

I was wondering if there is any option left for the author when a DOI dies? Every semester for the past two years I’ve been in contact with the publisher that acquired a journal in which I published. They keep saying they are “working with CrossRef in order to resolve the issue” but I think enough time has passed since December 2019. I understand the CrossRef term imposes certain obligations to members but I’m not sure how they can be enforced? The DOI in question is 10.5623/geomat-2010-0020 but it’s only accessible at https://0-www-nrcresearchpress-com.pugwash.lib.warwick.ac.uk/doi/abs/10.5623/geomat-2010-0020
I can forward the email exchange in private if detailed information is needed. Thanks!