Disable all plugins except Rehub framework. Then, update wordpress to actual 5.8 and try

Sorry i could not understand, which block you mean. Attaching the small screen recording about the trouble i am occurring with. Please find it.

Which block did you add on page?

Hi,

I recently updated my theme from themisle to rehub. I cannot able to write new post or update a post on my website https://productsreviewsblog.com/. Could you please help me out regarding this.