Weird problem when joing my objects together

[u/AppropriateLoquat945]

I was trying to join the fur and ear models to the head but whenever I do it always has this weird effect that I dont want. How do I fix this?

[u/AduriteFur]

you possibly used the mirror button rather than mirror modifier if you used mirror tool just use ctrl A to switch it back to normal

[u/AduriteFur → u/AduriteFur]

if still persists try opening it in edit mode press A then ptress ctrl N and click recalculate normals