Please someone should help me ...ypeError: Cannot read properties of undefined (reading 'length')

  useEffect(() => {
        // declare the async data fetching function
        const fetchData = async () => {
          // get the data from the api
          const params = {ethAddress: Address};
          const data = await'getFollowers', params);
         const userdata= await'getUser', params);
          // convert the data to json
          //const json = await data.json();
          // set state with the result
            for (let i = 0; i < data.followers.length; i++) {
             // dict[[i].id]=1;
               setfollowers_id(prevState => ({
        // call the function
          // make sure to catch any error
      }, [])

You can try to check the value of that variable.

Please help me …I am new to this …thank you

You can try to add some debugging with console.log

Please can you show me an example

An example: console.log(variable_name)

try to do as @cryptokid says and console.log(data.followers) it must be undefined

I’m not very sure how you structure your state, but if you don’t initialize anything in useState, then I also suggest you to initialize it with an empty array

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