Rental Income in a property partnership: Shariah ruling

Assalamu Alaikum wa Rahmatullahi wa Barakatuh, My name is Fahad Naseer and I am a resident of Islamabad. I am seeking your guidance in a Shariah matter (fatwa). I entered into a partnership agreement which was formally written on stamp paper and finalized in the presence of witnesses. According to this agreement: The first party provided the full capital for the purchase and renovation of a flat. The second party contributed their services, expertise, and time in the purchase, renovation, and sale of the flat. It was agreed that once the flat is sold, the net profit (after deducting all expenses) would be distributed between the first and second party in the ratio of 60% and 40%. This partnership has been ongoing for more than three years, but the flat has not yet been sold. During this time, the flat was rented out. Initially, when the second party asked about the rental income, the first party stated that the rent would belong only to the one who invested the capital, and that the second party would have no share in it. This understanding is also recorded in WhatsApp messages, including an audio statement from the first party and a written acknowledgment from the second party. Now, after a considerable period, the second party is claiming that since they are also part of the partnership, they are entitled to a share in the rental income as well, especially for the period during which the flat remained rented. Questions: In this situation, does the second party have any Shariah-based entitlement to the rental income? Is the initial verbal clarification (that the second party would have no share in the rent) considered binding in Shariah? Since the original agreement (sale of the flat) has not yet been completed, how should the rental income be distributed? Jazakum Allahu Khairan.