{re, err := ioutil.ReadAll(resp.Body)
a := json.Unmarshal(re, &accessobj)}
Getting error like
error: invalid character '<' looking for beginning of value
The error
error: invalid character '<' looking for beginning of value
Means that json.Unmarshal() tried to parse the content you passed to it assuming json format but it found a '<' character where it shouldn't have. As suggested, your input is not in json format, most likely an HTML document.
Take a look at this code:
re := []byte("<html></html>")
var accessobj struct{ X string }
a := json.Unmarshal(re, &accessobj)
In this example the content is HTML. Try to run it (on Go Playground) and you get identical error message:
invalid character '<' looking for beginning of value