Tax on a Minimum Wage Earner, Unpaid SSS, HDMF, Philhealth, Delay on BackPay

Hi! My company deducts my monthly salary with tax even if that I am just a minimum wage earner. I had concerned this to the HR department and they said that they would resolve and adjust it to our next pay day. I only had noticed it on my third month in the company however I have doubts that they were deducting tax with me since my first month on the company. Since the company were expanding their company in manila, on my 5 months stay with the company they were not regularly providing us payslip because the machine they should be using is still unavailable that time.

Question:
1. Can I ask them to provide me all my payslip since my start until end of contract with the company?

2. Since they were deducting tax on me and we all know that by law that they shouldnt deduct me tax. What legal action can I do with it?

3. I also had check my contribution and they I noticed that they haven't paid all my contribution its already four months since my end of contract?<< this is also the concern of other co-employees.

4. Is there a law stating that back pay should be paid 2 months after eoc or clearance? Its already 4 months since my clearance with this company but still i havent receive my backpay? I ask them how long it should be process and they replied 2 months only yet its already 4 months since my clearance. WTF!!!

Please help me guys!!