Context
In the company we all work remotely. There is no physical office. People are physically distributed over 3 continents right now. Let's say A, B, C.
Most of the people are sitting in continent B. It is kind of a company rule that the "official" working hours are the working hours of B. I put official between quotes because actually, people in continent A are not in this rule. They are expected to attend some scheduled meetings that happen more or less during time zone of B, but other than that it is accepted they will work most of the time in their time zone.
For what concerns me, when applying to the position, it was discussed and agreed by both parties that I would also stick to time zone B. But I live in C. I was questioned if that would be a problem, etc. At that moment I thought for me is no problem. Although living in C, I can stick to working hours, i.e. office hours of B time zone. And so went the last months.
However, after those last months, I realised I cannot really adapt to it and I started feeling worse and worse. It has arrived to the edge in which I started looking for other jobs just because of this time zone issue (just slowly searching, not like crazy!).
Other than that the job is ok.
Question
What would be a polite and effective way of handling the conversation to request to be able to work at least partially on my own schedule? I thought I might argument people in continent A are doing so. But I think they will argue back, because they have already kind of two time zones, it would be unbearable to handle another one.
I could just request it in a very plain way. But it is going to be a negative response I believe. This is because it was explicitly specified and discussed since the beginning that I should stick to time zone B. What I accepted. However, I have the right to change my opinion right?
So this question is not about if I should quit the job or not. Is about an effective way to ask for flexibility in the working hours.