Sorry, I realized my formula has problems looking for first number! Unless all your ID start with 01, it will return incorrect results!
Please use SM's solution, it is prefect. It looks for all the numbers and then returns first occurrence thanks to MIN and array formula.
What simple FIND ("x") does is returning first occurrence of "x" (say, 13) in string or #VALUE if it is not there, by putting multiple character to look for in brackets you tell FIND to look for all the characters, so function looks for "x", "y" and "z", and returns multiple results like: FIND({x,y,z}) = {13, #VALUE, 20} if we have X and Z in text, but not Y. Then, to make use of the result, you need array formula, or else you will only work with first result (that was the mistake I made).