Why does my Beverage refrigerator not cool after a period of time?

Why does my Beverage refrigerator not cool after a period of time?

To help us confirm the problem, could you please kindly help us answer these questions:
Q1:How long has this problem been occurring?
Q2: Did this problem occur when you first used it?
Also here is warm tips for you to use the item:
1.Installation Spacing: 1 inch of space should be left around the machine to facilitate heat dissipation.
2.Open early: allow at least 6 hours to cool completely. Please turn it on the night before planned use.
3.Check seals: Please check seals regularly and clean and replace as needed.
4.Check for obstructions: Regularly check the front and rear vents for obstructions (such as leaves and debris)