links to Mailpoet pages broken

After installing Mailpoet 3 (I have been used Mailpoet 2 for years) I made all my new forms and emails.

Everything looks working but, when a new subscriber receives the confirmation email with the activation link, this is what happens:

The link they should receive is this one (that’s what happens when I try it in the preview in setup options):

https://MYWEBSITE?mailpoet_page=subscriptions&mailpoet_router&endpoint=subscription&action=confirm&data=eyJwcmVjoxfQ

Nevertheless, what the get is:

https://MYWEBSITE/2020/03/07/subscriptions/?mailpoet_router&endpoint=subscription&action=confirm&data=eyJ0b2tlbiI6ImNsZHdzYTI2d2o0c2drZzRrc3dnb2c4bzhzZnY3IiwihaWOiJtYWxpBnbWFpbC5jb20ifQ

For some reason, some additional elements like a date or other things have been added to the url.

That happens also in all the links like unsubscribe or Manage subscriptions.

Could you give me some information to fix this issue? The pages exist and work but the url are wrongly generated.

Thanks again