Mails not sending after donation

I have three ways to give a donation on my site. Users are giving consent for a renewal after one year.

This all works, but the e-mails that I have put in my form are not sending.

Other e-mails from other forms on the same website do send. The e-mail ID’s I used are available and active.

[paytium name="Vriend van Fronik Zilver" description="Zilveren donatie"]
[paytium_subscription interval="12 months" times="" /]
[paytium_field type="label" label="Ik word Vriend van Fronik ZILVER en doneer jaarlijks:" amount="25" /][paytium_total label="" /]
[paytium_field type="firstname" label="Voornaam" required="true"/]
[paytium_field type="lastname" label="Achternaam" required="true"/]
[paytium_field type="email" label="E-mail" required="true" newsletter="mailchimp" newsletter_label="Ik meld me aan voor de nieuwsbrief" /]
[paytium_field type="text" label="Straatnaam" required="true" /]
[paytium_field type="text" label="Huisnummer" required="true" /]
[paytium_field type="text" label="Postcode" required="true" /]
[paytium_field type="text" label="Plaatsnaam" required="true" /]
[paytium_field type="terms" label="Ik geef toestemming voor een jaarlijkse automatische incasso en ik accepteer de algemene voorwaarden" link="https://www.fronikboerderij.nl/wp-content/uploads/2018/10/2018-10-01_Vriend-van-Fronik-Algemene-Voorwaarden.pdf" required="true" /]
[paytium_button label="DONEER €25/per jaar" /][paytium_emails id="2075, 2074, 2318, 4505" /]
[paytium_redirect status="failed" page_id="2147"]
[paytium_redirect status="expired" page_id="2158"]
[paytium_redirect status="paid" page_id="1094"]
[/paytium]

The page I need help with: [log in to see the link]