Cant acces the mailpoet from wordpress dashboard

I want to edit the emails forms i edited before with the mail poet plugin
i installed the mailpoet 3 pro plugin and use free sybcrition for now.

I already did some changes in the woocommerce email templates of complete order using the mail poet.
now i want to change the content there or delete the changes and i cant acces in any place in wordpress even if i delete the plugin and instal it again.
when im trying to instal the mailpoet 3 free plugin it says cant instal becuese libary alredy exist.
it crititcal to make all the changes so please let me know gow to fix it.
Thank you.

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