In 2016, I and a small group of players from the UK (David(me), Daina, Gemma, Chris E) travelled to Moscow for the 5th Russian Riichi Championship.
After worrying for weeks about my visa application (Did I fill in my travel history correctly? Did my signature match my passport's signature? Was the visa support voucher I paid for OK?) I received my passport with a visa with no problems.
My flight was Manchester -> Frankfurt -> Moscow, and I was able to meet Daina in Frankfurt which wasn't planned but was convenient as he was also my roommate. However, trouble struck when I arrived in Moscow!
My visa was OK, but my hair wasn't.
The chip on my passport had become damaged (After this trip I reported it and was able to get a free replacement passport because the chip was faulty) and I had short hair in my passport photo so the border agents weren't 100% sure it was me so I had to hold my hair back to emulate short hair for about 10-20 minutes until they were certain it was me.