python exchangelib FileAttachment not working while attaching multiple files from a list of names

Question

I have the code written below:

class SendEmail:
    def __init__(self, eSubject, eBody, eAttachmnts=None):
        self.eSubject = eSubject
        self.eAttachments = eAttachmnts
        self.eBody = HTMLBody(eBody)

    def setSend(self):
        print("Enter your Email Credentials")
        credsJson, usr, pWd = getCredential()
        self.setEmailParams(usr, pWd)

    def setEmailParams(self, usrNm, Pwd):
        creds = Credentials(usrNm, Pwd)
        config = Configuration(server=c.emailServer, credentials=creds)
        account = Account(
            primary_smtp_address=c.sourceSmtpAddress,
            autodiscover=False,
            config=config,
            access_type=DELEGATE,
        )
        self.sendEmail(account)

    def sendEmail(self, account):
        msg = Message(
            account=account,
            folder=account.sent,
            subject=self.eSubject,
            body=self.eBody,
            to_recipients=c.receipients,
        )
        for aName, aContent in self.eAttachments or []:
            msg.attach(FileAttachment(name=aName, content=aContent))
        msg.send_and_save() 

I'm calling this from my main script as :

attachments = []
for i in attachmntLst:
   with open(i, 'rb') as f:
      content = f.read()
   attachments.append((i, content))

emailObject = SendEmail(subjectLine, DF.to_html(), attachments)
emailObject.setSend()

subjectLine is a string. DF is a pandas dataframe. I want the dataframe to be printed in a tabular form as email body, hence used to_html(). attachmentLst is a list of filenames that I want attached to the email.

The code works well in sending the email with appropriate email body in tabular format. However no attachments are added to it, and I don't see any error messages as well. What is going wrong?