emailing changed after upgrade, now sends html code

Hi,
At e-Nable France we have been using UM since late 2015 and were very happy with it.
One of the functions we use is the ability to send an email to the admin team when a new user registers.
Since the update, instead of the nicely formatted and intelligible emails we used to receive when a new user registers, we receive a bunch of HTML code like below :
<div style=”max-width: 560px;padding: 20px;background: #ffffff;border-radius: 5px;margin:40px auto;font-family: Open Sans,Helvetica,Arial;font-size: 15px;color: #666;”>

<div style=”color: #444444;font-weight: normal;”>
<div style=”text-align: center;font-weight:600;font-size:26px;padding: 10px 0;border-bottom: solid 3px #eeeeee;”>E-nable.fr</div>

<div style=”clear:both”></div>
</div>

<div style=”padding: 0 30px 30px 30px;border-bottom: 3px solid #eeeeee;”>

<div style=”padding: 30px 0;font-size: 24px;text-align: center;line-height: 40px;”>Josselin Paille has just applied for membership to E-nable.fr and is waiting to be reviewed.</span></div>

<div style=”padding: 10px 0 50px 0;text-align: center;”>To review this member please click the following link: https://e-nable.fr/?page_id=274&um_user=ewaca</div&gt;

<div style=”padding: 0 0 15px 0;”>

<div style=”background: #eee;color: #444;padding: 12px 15px; border-radius: 3px;font-weight: bold;font-size: 16px;”>Here is the submitted registration form:<br /><br />
majeurok: Je certifie sur l’honneur être majeur<br />adresse-postale: 37b route de caen<br />country: France<br />role: um_maker<br />commentaires: Si vous savez modéliser en 3D, ou avez d’autres compétences que vous souhaitez partager, indiquez-les ici.<br />sendinfo_ok: Je souhaite recevoir par courrier électronique des informations relatives à l’activité de l’association e-Nable France.<br />disclaimer_valid: J’ai lu, compris et j’accepte sans réserve les informations ci-dessus. *<br />form_id: 270<br />date de soumission: 14 Jul 2018 18:22<br />datenaissance: 1984/09/11<br />user_login: ewaca<br />first_name: josselin<br />last_name: paille<br />user_email: [email protected]<br />code-postal: 14440<br />ville: douvres la délivrande<br />phone_number: 0678714726<br />mobile_number: <br />
</div>
</div>

</div>

<div style=”color: #999;padding: 20px 30px”>

<div style=””>Thank you!</div>
<div style=””>The E-nable.fr Team</div>

</div>

</div>

I understand it still contains the information, but is not readable and when I go to this particular email in UM settings it seems to have reverted to english.

Any help would be more than welcome.
Thanks for your time,
Thierry

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