What is the ruling on a person claiming entitlement to give the adhan in a mosque based on two Shar’i proofs, and who is most entitled to give the adhan, and are there conditions for the muezzin, and what if this claim is repeated daily?

The muezzin is required to be a Muslim, male, and of sound mind. It is recommended that he be melodious, trustworthy, knowledgeable of prayer times, and not blind. The most deserving of calling the adhan is the regular muezzin, and no one should call it before him unless he is absent and there is fear of missing the prayer time. It is permissible for there to be multiple muezzins in a single mosque.