Is my marriage valid with a woman whose guardian (her father) had converted to Islam, then claimed to be a Zaydi, and then showed words and actions that contradict Islam, raising doubts about his conversion to Islam?

For the marriage of a Muslim woman to be valid, it is a condition that her Muslim guardian or his agent concludes it. A disbeliever has no guardianship over a Muslim woman, by the consensus of the people of knowledge. If the guardian at the time of the contract prayed occasionally, then he is considered a Muslim by the majority of scholars, and the contract is valid. The fundamental principle is that a contract concluded by a Muslim is valid, and excessive scrutiny of past contracts opens the door to whisperings (waswas). If the guardian's condition changes after the contract, it does not affect its validity. It is appropriate to be gentle with him and teach him with kindness, as many are ignorant of their religious matters and grow up in environments that do not convey sacred knowledge to them. Such individuals are not deemed disbelievers until they know what the Messenger brought, and even if they are innovators, their Islam is better than their remaining in disbelief.