Hello everybody. I have published a hashlips contract (SIMPLENFT.SOL) derived from openzeppelin. the contract is already published on the polygon mainnet. unfortunately I have difficulty verifying it on polygonscan. not being a flat contract I am unable to carry out the procedure. I tried to make it flat using FLATTENER REMIX but I always find errors in generating the ABI. I'm not an expert, could someone kindly help me out?
Hi, welcome to the community! 
I think you can have a look at this tutorial:
And for the next time, please search at the forum at first, and then ask questions, thanks!
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