Prexy

Good day to all!

I am married to a British Citizen and I have just applied for a Spouse Visa early on February this year. I believe I have sent all the necessary documents and I have also done the Biometrics.
However, around mid-March, I received a letter stating that I have not complied with the Biometrics.
I sent them a letter with the receipt as proof that I have done the Biometrics, but re-registered again anyway just to play safe.
I was just wondering if anyone had a similar incident?
And how long do i have to wait in cases like these?
The agony of waiting and not knowing what's what is just killing me.
Please help.
Thanks in advance!