PayPal IPN problem

Message from the PayPal

Check your server that processes instant payment confirmations (IPN) from PayPal. IPNs sent to the following URL(s) are not received

URL(s) from PayPal email return error 500 with the error message to Woo logs: ERROR Invalid IPN call

paypal_plus-2021-02-09-6794283ee88f950d1f00a2ed388e6786.log

2021-02-09T15:12:53+00:00 ERROR Invalid IPN call
2021-02-09T15:38:42+00:00 INFO POST https://api.paypal.com/v1/oauth2/token
2021-02-09T15:38:43+00:00 INFO Response Status : 200
2021-02-09T15:38:43+00:00 INFO POST https://api.paypal.com/v1/payments/payment
2021-02-09T15:38:43+00:00 INFO Response Status : 201
2021-02-09T15:40:18+00:00 INFO GET https://api.paypal.com/v1/payments/payment?count=1
2021-02-09T15:40:19+00:00 INFO Response Status : 200
2021-02-09T15:40:59+00:00 INFO POST https://api.paypal.com/v1/payments/payment
2021-02-09T15:41:00+00:00 INFO Response Status : 201
2021-02-09T15:41:36+00:00 INFO GET https://api.paypal.com/v1/payments/payment?count=1
2021-02-09T15:41:37+00:00 INFO Response Status : 200
2021-02-09T15:47:13+00:00 ERROR Invalid IPN call
2021-02-09T15:47:27+00:00 ERROR Invalid IPN call
2021-02-09T15:48:28+00:00 ERROR Invalid IPN call
2021-02-09T15:51:47+00:00 ERROR Invalid IPN call

Can you help me with that? What goes wrong with IPN? It worked before February. Woocommerce and this plugin updated to the latest version

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