The maximum number of times a person can be recommended internally in a month is limited, and it seems to be about 5 times.

However, there should be no limit on other forms of application except internal referrals.

As long as you are not in the process, you can reapply.

After applying, if you fail the interview, as long as the previous position has completed the interview process, you can continue with the next interview. There is no need for a break in between.