this happens because Meta uses different AI servers and compliance bots to review ads, which can lead to inconsistent evaluation outcomes. differences in account history, fan page quality scores, or IP/domain reputation between the two accounts can also trigger a rejection on one while the other passes
Fb ad veterans confirm that this is very common due to Fb automated review system assigning ads to different inspection bots with varying sensitivity levels, combined with minor differences in account trust history, so simply appealing manually or slightly tweaking the creative copy will typically resolve the rejection.
To resolve this, simply request a manual review on the rejected ad - since the exact same creative was approved on another account, human reviewers will usually approve it upon appeal.
this is fairly typical with ad networks. the revieew process does not just take into consideration the ad that uh r putting up but it also takes into account the history of ur account the trustworthiness of ur account nd how things have been up until now. even two accounts that share the same campaign can receive different decisions since the back end evalluation process is unique for every account.