How to upload image for lobe trained model in local host?

[zydjohnHotmail]

Hello:
I have trained an image converter model in Lobe (version 0.10.1130.5). I also exported as an ONNX model. But I don’t know how to write some C# code to make some predication.
However, I found that I can use Lobe locally and post image to it. So I want to try this model.
I run Lobe in Lobe Connect, and I can see its local URL:
http://localhost:38101/v1/predict/2cc072ae-dbda-43c5-8db7-4c2515e0548d

However, the HTTP request is in this format:
{
"method": "POST",
"headers": {
"Content-Type": "application/json"
},
"body": {
"image": ""
}
}

I used one C# program to convert one of the training image to base64 string. Then I launch PostMan (Version 9.15.2) for Windows 10 to post the following Json data to local lobe connect end-point, like this:
{
"method": "POST",
"headers": {
"Content-Type": "application/json"
},
"body": {
"image": "iVBORw0KGgoAAAANSUhEUgAABAAAAAQACAIAAADwf7zUAAEAAE......=="
}
}

Then I quickly get response from lobe end-point, with the following Json reply:
{
"errors": [
{
"value": "{ "method": "POST", "headers": { "Content-Type": "application/json" }, "body": {
"image": "iVBORw0KGgoAAAANSUhEUgAABAAAAAQACAIAAADwf7zUAAEAAE......==" }}",
"msg": "Request body should be {"image": ""}",
"param": "",
"location": "body"
}
]
}

It seems Lobe connect does NOT recognize the base64 as an image.
Please advise on how to fix this?