net::ERR_HTTP2_PROTOCOL_ERROR" when using HTTP/2 with Application Load Balancer (ALB)

Despite enabling the HTTP/2 protocol in my Application Load Balancer (ALB) with a Target Group protocol version of HTTP/1.1, I encountered a "net::ERR_HTTP2_PROTOCOL_ERROR" instead of the expected error message when certain APIs responded with error codes due to incorrect icon selection. I tried by disabling HTTP/2 in the ALB, it is showing and responding with the correct expected error messages.