I assessed it at p=0.001 and did a clusterwise correction
The thresholding criterion you're using may be unnecessarily conservative, potentially limiting the informative value of your results. You might achieve better insights by exploring alternative visualization approaches for result reporting, as discussed here.
Additionally, the use of a canonical HRF could be reducing your detection sensitivity. Consider improving your modeling efficiency by adopting a more flexible HRF estimation approach, as outlined here.
Gang Chen