admin-ajax 400 Error

Hi I’m trying your plugin to speed up my site and I always get the 400 Error.

Request URL: https://www1.galerieschlossparz.at/wp-admin/admin-ajax.php
Request Method: POST
Status Code: 400 
Remote Address: 188.114.97.20:443
Referrer Policy: no-referrer-when-downgrade
access-control-allow-credentials: true
access-control-allow-origin: https://www1.galerieschlossparz.at
alt-svc: h3=":443"; ma=86400, h3-29=":443"; ma=86400
cache-control: no-cache, must-revalidate, max-age=0
cf-cache-status: DYNAMIC
cf-ray: 6fdd87648f9278ac-VIE
content-type: text/html; charset=UTF-8
date: Mon, 18 Apr 2022 12:50:56 GMT
expect-ct: max-age=604800, report-uri="https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct"
expires: Wed, 11 Jan 1984 05:00:00 GMT
nel: {"success_fraction":0,"report_to":"cf-nel","max_age":604800}
referrer-policy: strict-origin-when-cross-origin
referrer-policy: no-referrer-when-downgrade
report-to: {"endpoints":[{"url":"https:\/\/a.nel.cloudflare.com\/report\/v3?s=DAgnUBwm%2BL8R4mgNBs351SEBSbwh4a%2FKrRR8UWkFewUdtkkNYV3bNzHDbIp4fIFtj907RFDM7TqpNahKDsWzAtI0rWl0DBDlJ9OCknKszlvycCu1uf9nmbSvdBI%2BH1koKy3yHL3OuxtAZAlgEw%3D%3D"}],"group":"cf-nel","max_age":604800}
server: cloudflare
vary: X-Forwarded-Proto,Accept-Encoding,User-Agent
x-content-type-options: nosniff
x-content-type-options: nosniff
x-frame-options: SAMEORIGIN
x-robots-tag: noindex
x-xss-protection: 1; mode=block
:authority: www1.galerieschlossparz.at
:method: POST
:path: /wp-admin/admin-ajax.php
:scheme: https
accept: */*
accept-encoding: gzip, deflate, br
accept-language: de-AT,de;q=0.9,en-AT;q=0.8,en-US;q=0.7,en;q=0.6,de-DE;q=0.5,es;q=0.4
content-length: 147
content-type: application/x-www-form-urlencoded; charset=UTF-8
cookie: wordpress_sec_462bfd8732e8c35a69077642be91ca5e=icniv%7C1651488088%7CQsHJbnUy4DGk8xL9THKTzkmCGesGCgewaSOZ8wLgI6V%7C83b430c11a1202a830d8df383f4dbd1e757f34c871c042df461ae5a730ba6973; cookielawinfo-checkbox-necessary=yes; wordpress_test_cookie=WP%20Cookie%20check; wp_lang=en_GB; wfls-remembered-BmuPWPeowoMsWQ9ZktdYDw=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpdiI6IlhNdU0xQzlTSU9rdzNCa1wvRE9DcVpRPT0iLCJfZXhwIjoxNjUyODcwNDg4fQ.hi5rVCHWGsBtwCi0tXN-aadqQ7tyCoSedpc-n1Qg6v0; wordpress_logged_in_462bfd8732e8c35a69077642be91ca5e=icniv%7C1651488088%7CQsHJbnUy4DGk8xL9THKTzkmCGesGCgewaSOZ8wLgI6V%7C4be13fe8980d5a5050b3a8ec143a515b3cad45014dbb89c35e9ba8c0cf4b2901; tk_ai=woo%3AOEZUSYiUaNl%2FrFtorZUGpxH5; wp-settings-1=libraryContent%3Dbrowse%26ampamp%3Dundefined%26ampimgsize%3D%26ampeditor%3Dtinymce%26imgsize%3D%26editor%3Dtinymce; wp-settings-time-1=1650278495; _gid=GA1.2.1747129287.1650278580; cookielawinfo-checkbox-analytics=yes; CookieLawInfoConsent=eyJuZWNlc3NhcnkiOnRydWUsImFuYWx5dGljcyI6dHJ1ZX0=; viewed_cookie_policy=yes; _ga=GA1.1.1370106412.1650278580; wfwaf-authcookie-256b675cd50c0cacbac6037fb9d3a9de=1%7Cadministrator%7Cmanage_options%2Cunfiltered_html%2Cedit_others_posts%2Cupload_files%2Cpublish_posts%2Cedit_posts%2Cread%7Ce4b30e5cfac0fddc5c5f9f1e41ffcae588430c66b5823ffa1f30c8811315932e; _ga_V5W766BPW8=GS1.1.1650285891.2.1.1650286123.0; et-editor-available-post-73-fb=fb
origin: https://www1.galerieschlossparz.at
referer: https://www1.galerieschlossparz.at/wp-admin/post.php?post=73&action=edit
sec-ch-ua: " Not A;Brand";v="99", "Chromium";v="100", "Google Chrome";v="100"
sec-ch-ua-mobile: ?0
sec-ch-ua-platform: "Windows"
sec-fetch-dest: empty
sec-fetch-mode: cors
sec-fetch-site: same-origin
user-agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/100.0.4896.88 Safari/537.36
x-requested-with: XMLHttpReque

Can’t seem to get it running. Any help?

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