We are also experiencing this with WordPress 5.0.2 & 5.0.3 and ACF 5.8.0-beta3. Our sub-fields within repeaters do not seem to save correctly. Returning to the edit page displays blank fields and the data is not displayed on the front end of the site. No errors are reported in the PHP error log.
Any word on looking into this problem?
Welcome to the Advanced Custom Fields community forum.
Browse through ideas, snippets of code, questions and answers between fellow ACF users