ものだから

「ものだから」 is used to provide a reason or explanation, often for something that is considered objective or unavoidable. The clause that follows 「ものだから」 does not express the speaker's intentions, requests, or commands. It is often used in writing or casual speech. To make it more polite, you can use 「ものだから」
In addition to 「ものだから」there are other forms with similar meanings such as 「もんだから」「もので」「もんで」「もの」...