Ask the wallet you're sending from why they gave you an error.
nostr:npub1mutnyacc9uc4t5mmxvpprwsauj5p2qxq95v4a9j0jxl8wnkfvuyque23vg when I send sats to mutiny why does the sending wallet give me a error / failed message but the transaction completes just fine on the mutiny side?
Discussion
This also happened to me. Sending from my node using RTL to Mutiny. The sending got stuck then I received an error but the payment went through.