nostr:npub1ll3r7gr0u3afx6ap65xsrjphq7pafpyjq6jyfhd5peuq5v69lnzq4p7yhh you can try putting the magnet in place and heating it with a soldering iron, and it will sink into the PLA and glue it there.

Be careful not to overheat it, or your magnet will lose its magnetism.