Second time H1B stamping

Here is my H1B journey so far

Apr 2012 - Desi consulting Firm applied for my H1B and it was approved .

Dec 2012 - Went for Stamping and got stamped until 2015

9th Apr 2013 - Came to USA ,got the SSN.

May 2013 - client didn’t place me on any project hence they didn’t run payroll for me.

June 1st 2013 - Got the new Job and H1B transferred to new employer.Got the i94 attached with my H1B .Since then I was working for this new employer.

August 2013 - Desi Employer revoked my H1B.

Mar 2014 - Went to India and came back to USA with my new i797.

Jun 2019 - Currently I have Valid i797 till Jan 2022 with approved i140 .

Please go through my case and advise . Planning to go to India in June /July .

Can you please tell me what to tell if they ask about my Old employer ?Will I get any issues during Visa stamping ?

While we cant rule out any question by USCIS at any stage, being HONEST is the mantra if you need to reply something. You dont need to tell anything if not asked.
Having said that, there are chances that you may be asked about your previous H1B details, you can tell them that your employer didnt pay and you found an eligible next employer and working as per the H1B conditions. I dont think YOU will have any issues but your previous employer only.
Dont worry, just be prepared for what you may expect questions, be honest when you must reply.