Elias here with Shopify Support. Thank you for reaching out to Shopify!
Sorry to hear that you're unable to login to your store. I understand you're unable to log into your account. Just to confirm, does the issue persist on another device or with a different browser?
That being said, this issue may be related to your browser's cookies and caches. We've seen some success with resolving this issue after clearing the browsing history. Can you give that a try?
If the issue continue to persist, please let me know and I'd be happy to take a closer look!