I am using an HTML Text widget to format how my email should look like. This gathers details from a gallery & collection, into the formatting that I've created. I tried changing background color of cells, font size, border colors, etc. (see image attachment html)

"<font size='6px'><table width='100%' border='1' cellpadding='5' style='border:1px solid white; border-collapse:collapse'>
<tr style='background-color:#911813'>
<th style='color: #FFFFFF'>" & Label_Header & "</th>
</tr>
</table> </font size>
<table width='100%' border='1' cellpadding='5' style='border:1px solid white; border-collapse:collapse'>
<tr style='text-align:left'>
<th><i>"& Label_Date & "</i></th>
<th></th>
</tr>
<tr>
<td>" & Input_Date & " </td>
<td> <img src='Logo_Quistor.png' style='max-width:50%'></td>
</tr>
<tr style='text-align:left'>
<th><i>" & Label_User & "</i></th>
<th></th>
</tr>
<tr>
<td>" & Input_User & " </td>
<td>Customer logo</td>
</tr>
</tr><tr>" &
"</table>"
Then with a button, send this formatting as an email with the Outlook365 connection (see image attachment Outlook). However it disregarded all of my formatting and now looks totally different.

Office365Outlook.SendEmailV2(
User().Email,
"Test Customer Daily Healthcheck Report",
HtmlText1.HtmlText, {Attachments:LogoCollection, IsHtml:true})
What am I doing wrong here?
Thank you!