Yes, Albert Einstein, like any other scientist, made mistakes throughout his career. It is important to remember that making mistakes is a natural part of the scientific process, and even the most brilliant minds are not immune to errors or inaccuracies.
One notable example of Einstein's mistake was his introduction of the cosmological constant. In 1917, Einstein added a term known as the cosmological constant to his equations of general relativity in an attempt to account for a static universe. Later, when it was discovered that the universe is expanding, Einstein referred to the introduction of the cosmological constant as his greatest blunder.
Additionally, there were some instances when Einstein's ideas or theories were initially met with skepticism or later proven incorrect. For example, Einstein's proposal of the existence of "gravitational waves" in his general theory of relativity was met with skepticism for several decades until their direct detection was achieved in 2015.
It is worth noting that despite these mistakes or initial challenges, Einstein's contributions to physics and our understanding of the universe remain significant. His theories of relativity revolutionized physics and continue to be fundamental in various fields of scientific research.