Hi, sorry for the delay responding, I have been spending some days out of my city.
I haven’t used bitmart but the error says: uid credential is missing, so it requires it apart from api and secret.
Also note that this exchange is not a certified one, that means that there is high % of having issues and need fixes.
https://gunbot.shop/list-of-supported-exchanges-gunbot-v16/
Other thing:
1. How to apply for APIKEY?
Answer: API application site: https://www.bitmart.com/api After successful application on the website, please keep your access key, secret key and memo. Users in Hong Kong may also have faster access through https://www.bitmart.news/api.
9. What is memo?
Answer: Memo is provided by users themselves. It will be used in the signing of the interface.
https://developer-pro.bitmart.com/en/part1/question/apikey.html