Invalid mime format - soap

Question

while uploading file to irs in mef ifa platform, when file is uploaded its preliminary validation failed and an error occurred "invalid mime format".
I have tried in many ways and with different formats but not fixed.
Here is my file to transmit
MIME-Version: 1.0
Content-Type: multipart/related;
boundary=MIMEBoundary941; Content-Type: text/xml; charset=UTF-8
Content-Description: Transmission File containing one Submission.
X-eFileRoutingCode: MEF
--MIMEBoundary941
Content-Type: text/xml
Content-Transfer-Encoding: 8bit
Content-Location: Envelope941
<?xml version="1.0" encoding="UTF-8"?>
<SOAP:Envelope xmlns="http://www.irs.gov/efile"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:SOAP="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:efile="http://www.irs.gov/efile"
xsi:schemaLocation="http://schemas.xmlsoap.org/soap/envelope/ ../message/SOAP.xsd
http://www.irs.gov/efile ../message/efileMessage.xsd">
<SOAP:Header>
<TransmissionHeader>
<TransmissionId>******</TransmissionId>
<Timestamp>2022-07-18T14:05:57+06:43</Timestamp>
<Transmitter>
<ETIN>******</ETIN>
</Transmitter>
</TransmissionHeader>
</SOAP:Header>
<SOAP:Body>
<TransmissionManifest>
<SubmissionDataList>
<Count>1</Count>
<SubmissionData>
<SubmissionId>*******************</SubmissionId>
<ElectronicPostmark>2022-06-30T14:05:57+06:43</ElectronicPostmark>
</SubmissionData>
</SubmissionDataList>
</TransmissionManifest>
</SOAP:Body>
</SOAP:Envelope>
--MIMEBoundary941
Content-Type: application/octet-steam
Content-Transfer-Encoding: Binary
Content-Location: SubmissionZip
<<ZipFile here >>
--MIMEBoundary941—