Wish complaint: Fined $500 accused of false tracking

I posted an item as a merchant on wish to a customer in Ireland with Royal Mail uk.I have the receipt and tracking.The item was in the network for a while probably because of brexit.I tracked the item and it said it had gone to Russia(ROYAL MAIL NOT MY FAULT)I contacted the buyer and told him what was happening and he is entitled to a refund.He said he will wait a while.Anyway the item did turn up on the 26th March 2021
The buyer ed he had received the item .On the 25th March Wish fined me $500 saying my tracking was fake .That is a very Derogatory remark .I have contacted my wish manager and she has said she will have the money returned.After 10 days its not turned up.In the mean time wish have refunded the buyer and I lost the item and the postal cost
.Also they again find me a further time for late delivery so they are admitting it was delivered.My intentions are to take legal action but I am not sure who to contact as I will take them to a small claims court im the UK.I am honest and the delivery is out of my hands once posted
I have attached full tracking in Photo proof
I have the full tracking in many screenshots but I can only upload one .I have enclosed the Postal receipt it shows the tracking number so anyone can follow this.