State Bank Of India [SBI] — Signature issue at bank

Address: 403510

I have issued a cheque of SBI bank to Holy family school for the term fee of my son but by cheque has been return back by State bank of India by giving reason that my sign differs with specimen signature with bank However when i have contacted with the bank my sign matches with specimen signature with bank but manager told me that cheque is cleared at bombay branch we cannot do anything about this.i have to face lots of problem becauase of this which are as follows:
1) Delay in paying term fee of my child.
2) simply waste of time without my fault.
3) Clearing bank of Holy family school is Bank of india.They have charge me fine of Rs 300/-.
4)I have to pay term fee by taking Demand Draft from SBI for that i have to wait for around 5 hours because printer is not working