I have a three related tables: School, Pupils, and Results:
School > Pupil (One to Many) - linked by School code
Pupil > Results (One to Many) - Linked by Pupil ID
I have a simple scatter plot of pupil results filtered by subject. I made a custom tooltip which contained measures relating to the result (which work fine) and a card visual which contains the 'first' Pupil Name from the related Pupils table. This worked fine until yesterday... now the pupil name doesn't change when different results are selected in the scatter plot (the result measures still work correctly).
'Keep all filters' is still set to "On". I have a very similar setup in another workbook and it functions correctly. I tried creating a new tooltip but it still behaves incorrectly.
The only change I have made recently is changing the spelling of a column in the Pupil table of power query - I updated/replaced a filter visual on the page to reflect the new column. Would that have broken it? This column was not in the tooltip, the scatter plot or any of the measures used in the tooltip or scatter plot.