They were on a list of names allowed to cross into Egypt but the gates did not open as expected.
Nearly 100 Brits passed through the day before.
A Foreign Office statement said: “This continues to be a complex and challenging situation and we are pressing for its reopening.
“It is vital that the safe passage of people, and humanitarian aid, can continue.”
Meanwhile, shelling across Gaza continued.
The Sun on Sunday witnessed explosions and plumes of white smoke from its vantage point in Sderot, in southern Israel.
Most of the 30,000 residents of the town, where about 40 people were killed on October 7, have fled, but a few have stayed put.
Supermarket worker Moria Cohen, 24, said: “When it happened I was having panic attacks but this is my home.”
Retired caretaker Vladimir Kreiderman, 65, was sitting outside his house when Hamas rockets destroyed homes on either side of him.
He said: “They are not driving me out of my house.”
There was also more shelling on the Israel-Lebanon border yesterday where IDF forces have been fighting Iranian-backed Hezbollah.
US intelligence fears that Russia’s Wagner mercenary group — which has played a vital role for Vladimir Putin in Ukraine — will send air defences to Hezbollah’s militia forces in Lebanon.