Version 1.8.1 Not Retrieving Rates from R+L API

I have a site that is using the R+L Carriers plugin and it got automatically updated to use the latest version of the plugin. After that update WooCommerce stopped displaying shipping rates. We only use R+L Carriers for the rates on the site in question. Rolling back to a previous version (1.7.3) resolved the issue. I enabled the debugging option while still on 1.8.1 and the following is what was output.

For now we have turned off automatic updates of this plugin and are staying with version 1.7.3 until the issue is addressed.

R+L REQUEST:
{
    "RateQuote": {
        "CODAmount": 0,
        "Origin": {
            "City": "Stratford",
            "StateOrProvince": "CT",
            "ZipOrPostalCode": "06615",
            "CountryCode": "USA"
        },
        "Destination": {
            "City": "New Britain",
            "StateOrProvince": "CT",
            "ZipOrPostalCode": "06051",
            "CountryCode": "USA"
        },
        "Items": [
            {
                "Width": "",
                "Height": "",
                "Length": "",
                "Class": "70.0",
                "Weight": 200
            }
        ],
        "OverDimensions": null,
        "Pallets": [],
        "AdditionalServices": [],
        "DeclaredValue": 1085
    }
}
API Error:
API Error:
API Error:
R+L RESPONSE:
Array
(
)
R+L REQUEST:
{
    "RateQuote": {
        "CODAmount": 0,
        "Origin": {
            "City": "Stratford",
            "StateOrProvince": "CT",
            "ZipOrPostalCode": "06615",
            "CountryCode": "USA"
        },
        "Destination": {
            "City": "New Britain",
            "StateOrProvince": "CT",
            "ZipOrPostalCode": "06051",
            "CountryCode": "USA"
        },
        "Items": [
            {
                "Width": "",
                "Height": "",
                "Length": "",
                "Class": "70.0",
                "Weight": 200
            }
        ],
        "OverDimensions": null,
        "Pallets": [],
        "AdditionalServices": [],
        "DeclaredValue": 1085
    }
}
API Error:
API Error:
API Error:
R+L RESPONSE:
Array
(
)