slows down the admin panel

When working with this theme, I encountered a problem with the extremely slow admin panel. I didn’t immediately realize that it was the problem. But then I installed a clean WordPress for testing. I deleted all the plugins there and simply installed several themes one by one. They all worked fine in the admin panel, except for the Easy Store theme. This is a blow for me, because I have already managed to make part of the site and now I will have to start everything from scratch, because it is impossible to interact with such a speed of the admin panel.