Hi I was requested my employer to sign unpaid...

We would like to inform you that according to the UAE Labor Law, a worker who works under an indefinite employment contract that shall notify the employer of his desire to terminate the employment contract. The notice period shall at least be thirty days. If either party fails to take that period into account, a compensation shall be paid to the other party called a compensation for the notice period.
The employer must pay the worker’s salary for the notice period, and if the employer does not pay this salary, in that case the worker must file a complaint with the Ministry of Human Resources and Emiratisation
Here are the texts of the UAE Labor Law relating to your inquiry:
Article (116):
Where a contract is revoked by the worker for reasons other than those stipulated in Article (121), he shall be required to compensate the employer for any damage the latter sustains as a result, provided that the amount of compensation shall not exceed half a month wage for three months or for the remaining period of the contract, whichever is shorter, unless otherwise stipulated in the contract.
Article 117:
1. Either the employer or the worker may terminate an indefinite term contract for a valid reason at any time following its conclusion, by giving the other party a notice in writing at least 30 days prior to termination.
2. For the daily-paid workers, the notice period shall be as follows:
• One week: if the worker has been employed for more than six months but less than one year.
• Two weeks: if the worker has been employed for not less than one year.
One month: if the worker has been employed for not less than five years.
Article 118:
A contract shall subsist throughout the notice period referred to in the preceding article and shall terminate only on expiry of that period. The worker shall be entitled in respect of the notice period to full pay, calculated on the basis of his last wage, and shall continue to perform his duties during that period if the employer so requests. The Parties may not agree to waive the notice requirement or to reduce the notice period; however, they may agree to extend the period.
Article 119:
If either the employer or the worker reduces the period of, or fails to serve a notice of termination on the other, the forbearing party shall pay the other a “compensation in lieu of notice”, irrespective of whether or not the other party has sustained damage as a result of such failure or short notice. The said compensation shall be equal to the worker's wages in respect of the entire or reduced period of notice. Compensation in lieu of notice shall be calculated on the basis of the last wage received, in the case of monthly, weekly, daily and hourly paid workers, and on the basis of the average daily wage referred to in Article 57 of this Law in the case of those paid on piecemeal.

Not assigning the worker any work is a matter that does not mean the worker in anything.
We do not recommend signing any papers