Force to complete bet

I was playing live no limit hold'em tournament in LA.
Blinds: SB1500, BB3000
Anti 300
I am middle position. No one called or raised in front of me. I look down at AXo and figure I can steal the pot from the BBs. I announced I was raising, and push forward 7.5K (2.5bb) Seven 1k and one 500 chips. The dealer said I need to complete my bet??? I didn't know what he was talking about. I should be able to bet whatever I like as long as it's more the minimum raise. I ended up removing my 500 chip and replacing with 1K chip, tor a total of 8K. After a short argument with the dealer, one player calls and the BB moves all in... I have to fold because I was lost on what was going on and didn't have a good read on the other two in the hand.
I looked all over the internet for something. Closes thing I could find was called on string betting. I announce I was raising (no amount) and in single motion moved 7.5K chips in middle of the table. After I move the chips, I said the amount, to 7.5K. I couldn't find anything saying that did something wrong. Please help.

Thank you,
Jeremy

you did nothing wrong unless there is a specific house rule that after a certain level you cannot use the 500 chips to make bets, only to put out blinds, but this should be made clearer a long time before (at the start of the level)

if it happens again insist the dealer calls the floor

Is it possible the blinds had just gone up to 2K/4K? Otherwise your bet should have been legal at 7.5K.

This.

But if you're certain the level had not increased, then you should have asked for the floorperson.

If blinds were 2k/4k and you said "raise to 7.5 thousand" would your raise still stand and also would the dealer have to say "that isn't the min raise"?

You would be forced to raise to 8K.

I don't think the blinds increased yet. I just moved from a different table and had clear look at tournament timer. This first time I have played there and they may have house rules that I don't know about. I will ask one the dealer before tournament next time a play there. Thanks for everyone responses.

Jeremy

First time hear about that, probably some house rules, but if 500 chips are in play and ante is 300,they are valid anyway. Maybe dealer made mistake.