Can I get experience certificate through CADSoft Technologies

I am working in a company named as CADSoft Technologies, and I had joined this organization in 21 Jan, 2013. Now, I have completed my 4 years and 8 months in this company so I am eligible for gratuity benefits from the company. But, 2 years back company send a mail at the time of increment and mentioned your employment transfer to another company named as TIET. Both the companies manage by same people at the same place. They did not provide any new offer letter and did not signed any documents from the employees about this transfer. Now, company management says that you are the employee of the TIET and we have sent you a mail regarding this 2 year back. Same time they are running both the organization currently as well. They are running consulting work under the CADSoft Technologies and Training work under the TIET. I am also filing my ITR on the behalf of CADSoft Technologies last 4 years. They did all these thing (changing in the name of the company) to hide the government tax.