Hi Maciej,
I have fixed the problem using “pretty permalinks” settings in wordpress. It was very disruptive since because of this my site was not live for the day and I was in the middle of pitching websites for guest posting on them, so they would not have been able to read my blog.
For the disruption you could offer to help me by referring me to a guest post website that would accept a guest post of “my fiery blog material to peak their revenues”. Again my site is at https://3dresearchspecs.com . The type of websites to do this would be Casual Dating Advice ones.
Regards, Marc (@curioushat)