You were using an old link before. Yesterday you used a new link.

The price of SPI goes up. When you paid yesterday, you paid 5.75 STEEM. The 4 weeks before that when you were using an old link, you were paying 5.50 STEEM. The cost of each SPI is 1.15 STEEM

5 weeks ago SPI's costs 1.10 STEEM
4 weeks before that they costs 1.05 STEEM

Tomorrow they will cost 1.20 STEEM as we have issued 50k tokens and the price has increased.

Hope that makes sense