Thank you for the question. I am sorry to hear about this matter. If you are on the birth certificate then you have parental responsibility. If the mother has knowingly put false information on the birth certificate this is a criminal offence. However to heal with this matter, you will require to raise and action in the Sheriff Court. The Court can legally order a paternity test. If the child is yours, you have rights you can enforce if you are being denied contact etc.
I shall provide you with a helpful link that will assist you in finding a solicitor/representative near your local area. This will provide you with someone nearby your area who can assist you if required.
I hope this information proved helpful. You will find a local solicitor who deals with these matters on the law society webpage which is as follows;
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