Protest a Game

Hello, my chess name is DustyTyalice! I was playing an opponent that went by the name of [Name removed- Moderator] around 12:30 today. I was clearly beating him for instance he only had his Queen left  and I had 4 pawns and a Queen. The four pawns was all ready to Queen but the system would let me to Queen not one of them. Later, a long time later it looked like the system was going to let me Queen. When I tried, I went back to clear board that was ready to play. I felt like I was cheated because when my opponent Queen he was able to Queen successfully. But, when I tried I couldn't! What happened and why wasn't I able to Queen?

[The site has a policy that naming and shaming is not allowed. If you think your opponent cheated, click on "Help & Support" at the bottom of the page, then on "Contact Staff" in the lower left and select the Report Suspected Cheating category. If nobody can explain the issue here and you think there was a bug in the programming select Technical Support & Bug Reports - Moderator]