Problem with subscribing

This is the error i get in my LOG file in my page:

[2019-06-06 07:46:43] ERROR: Form 174 > Mailchimp API error: 404 Not Found. Resource Not Found. The requested resource could not be found.
Request: PUT https://us20.api.mailchimp.com/3.0/lists/343ed3e35d/members/10b170593bf2b72fe48ae9827e13671d – {“email_address”:”cont***@tr**********.mk”,”interests”:{},”merge_fields”:{},”status”:”pending”,”email_type”:”html”,”ip_signup”:”195.26.144.6″,”tags”:[]}
Response: 404 Not Found – {“type”:”https://developer.mailchimp.com/documentation/mailchimp/guides/error-glossary/”,”title”:”Resource Not Found”,”status”:404,”detail”:”The requested resource could not be found.”,”instance”:”f08fbe9a-33b1-4b82-ac24-5d4f0f6c54e6″}

And this is the error i get in my MailChimp account:
Date/Time Result Throttled? Source IP Method Format Exec Time User Agent Ver Response
2019-06-06 07:54:37 GMT nope 67.220.182.10 PUT /lists/…/members/…/ php 0.017s mc4wp/4.5.2; WordPress/4.9.10; https://pope4.pavitrans.mk 3.0 The requested resource could not be found.
2019-06-06 07:54:37 GMT nope 67.220.182.10 GET /lists/…/members/…/ php 0.023s mc4wp/4.5.2; WordPress/4.9.10; https://pope4.pavitrans.mk 3.0 The requested resource could not be found.
2019-06-06 07:54:37 GMT nope 67.220.182.10 GET /lists/…/ php 0.016s mc4wp/4.5.2; WordPress/4.9.10; https://pope4.pavitrans.mk 3.0 The requested resource could not be found.

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