Sir, Hope you have checked about the company before accepting the said offer.,hope you have all the relevant documents in your hand so that you can join the said company may be on the future date as communicated to you by them, you are required to be in constant contact with the new employer., and make them aware that you are available to join on the given date. You can also communicate to them that basing on their offer you had got your re-leaving and now ready to join., in the same manner you can also mention your financial concern.,
Does it Happen is your 1st Question, as it is evident that it happened to you only, and your 2nd question if they further delay the DOJ, you are advised to take all the communication in writing and signed by a responsible official and be on a company letter head with duly stamped. and your 3rd question what will be the options be left with, i would say you must give them a minimum of 2 attempts, the 1st attempt is over and 2nd is running in your case, if they still post phone the DOJ, you will have to take it that they are not really interested in you to be on their board. at this juncture except for hoping for the best and making an alternative trials you have no other options to stabilize your carrier and daily living (Financial part). I would seriously recommend you to visit their office and meet the concern incharge and take the assurance on document. this is suggested to safe guard your personal interest. and it is also recommended to have a cross verification about the company and its reputation both in the market and as well as in the job seekers crowed.
Wishing you all the very best in your carrier.
Regards
J SriRam