In the bidding documents, the project manager's qualification and performance bonus mentioned that the contract amount was ≥ 5 million, which was questioned by bidders. How to reply to questions?

This is a bonus item, not a qualification requirement, and there is no exclusivity. "The contract amount is more than or equal to 5 million". My understanding is that in the performance of the project manager entrusted by the bidding unit, those who have undertaken the project manager in projects with contract amount greater than or equal to 5 million will get extra points. So here, first of all, you should describe what you want to express clearly; Secondly, it is better to write down the deadline and add "20 10 1 till now" in front of it, which is equivalent to requiring similar experience within three years.

Look at your bidding documents first. Did you make your meaning clear? If not, modify it.

If you feel clear, you can reply directly. The bonus item is neither a qualification requirement nor a substantive requirement. The questioning unit can entrust an experienced manager to undertake this task, and can also influence its score by adjusting the tender offer.

As far as the current market is concerned, I suggest you add a requirement: the project manager (and other key positions in the team) entrusted by the bidder in the bidding documents cannot be replaced once winning the bid. Because, at present, in the construction process after winning the bid, many tendering units have one set of bidding documents and another set. Few of these qualified or experienced "industry experts" can always stick to their posts.