The problem come from “Get Data Table Row” node. Each time, the blueprint is reloaded, that node doesn’t make the link between the “Data Table” and the “Out Row”. The “Out Row” becomes invalide and the link between “Out Row” and “Break Row” is no longer valid and is broken.
A manual update temporarily solve the problem by deleting, compiling and then re-adding the “Data Table” link.
One solution would be to change the node to an automatic update is made before the test links between nodes.
(french writer… sorry ^^)