How long to wait to send friend requests in temporary block?

I sent friend requests and I received a temporary block without giving any time limit.

When can I again send friend requests?

Try again after a couple of days. I don’t think they give you the exact time when the block will be lifted. The only way is to check from time to time.

you need to figure out what you did wrong first in terms of settings and your configuration/setup then give the account a few days’ rest and try again and see how it goes.