Please use this as below 
<html>
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
</head>
<body>
<p>Dear #CUSTOMER#,</p>
<p>Thank you very much for contacting us. The ticket #TICKETID# status has been changed to #STATUS# and we would like to get your feedback on our customer care operations in order to serve you better in future. </p>
<p>Please provide your valuable feedback by click on this link: #SURVEYID1# </p>
<a href="https://{/FormCampaignExecutionPlaceholder/Survey/SurveyID}1">Please Complete a Survey</a>
<p>Thank you,</p>
<p>Customer Care</p>
</body>
</html>
The highlighted section is what is missing / wrong in your snippet, i have tested the HTML code above and this works fine and should work for you as well