Product: Bank account or service

1 : I received promotional offer from PNC Bank on XX/XX/XXXX. It indicated I will receive 1.34 % promotional interest rate for the first 6 months and the same account will get 0.74 % APY after first 6 months. 
Please find the document in document 1 in the attachment and pay special attention in note 2 which refers to the standard balance tiers in the 0.74 % APY in PNC 's offer after 6 months. 

2 : I transferred assets to the qualified account before the deadline on XXXX/XXXX/XXXX. and I received the 1.35 % APYE in the first 6 months from PNC bank as promised. 
Please find the doucment of my XX/XX/XXXX PNC bank statement in the attachment. Please pay special attention to the interest summary that shows APYE is 1.35 % which is slightly higher than the 1.34 % as promised. The interest paid in this month is {$160.00}. 

3 : The first 6 month expired in XX/XX/XXXX. The interest rate shall drop to 0.75 % after the first 6 months for this account according to the promotion. Instead, PNC bank only gave ~0.12 % APYE. Please see my XX/XX/XXXX monthly statement in the document 3 in the attachment. 
Please pay special attention to the interest summary 0.12 % APYE and the interest paid in this month is {$22.00} which is less than XXXX of the interest in XX/XX/XXXX and XX/XX/XXXX is with much higher balance. 

I have contacted PNC bank since XX/XX/XXXX and talked to PNC bank retail escalation group several times. They have been postponing the answer until XX/XX/XXXX. I received a voice message. The voice message basically refuses to make the interest rate adjustment and told me the rate referenced in the promotion is yearly average. PNC Bank indicated that the interest 0.74 % APY after 6 months is averaging with the prior 6 months interest rate of 1.35 % so the rate after 6 month is actually 0.12 % APY and no adjustment will be made. 
The voice message in attached in the document 4. 
Their explanation is totally unacceptable to me : A : As the rate refers in promotion 1.35 % for the 6 months is APY as shown in my XX/XX/XXXX months statement and the 0.12 % is also APY in the XX/XX/XXXX statement. They are the same APY. The after 6 months promotion rate 0.75 % is also APY and why does not show in my XX/XX/XXXX statement as 0.75 %, rather it showed 012 %? 

B : The interest paid in the XX/XX/XXXX statement is more than XXXX of my XX/XX/XXXX for one month. The balance of XX/XX/XXXX is much higher than the balance in XXXX. If XXXX interest 1.35 % APY is consistent with the 0.75 % APY after 6 months according to the promotion rate, the interest paid in XX/XX/XXXX shall be much higher. 

C : I do not believe any bank will refer the APY that is balance with the prior interest rate it offers. For example, instead of 1.35 % APY in the first 6 months, PNC bank can offer 5 % APY in the first 6 months and 0.74 % APY after 6 months to lure customer. If PNC Bank explanation make senses, does it mean consumer have to pay negative interest rate to PNC Bank after 6 months. I believe that PNC bank explanation is deceiving and telling lie to customer. The 0.74 % APY shall refer to the interest rate after 6 months not averaging with the interest rate in the first 6 months. It is also clearly suggested in the note 2 of their promotional offer. The offer stated, the introductory interest rate of 0.74 % does not apply to the first XXXX balance teirs. The account between XXXX receives 0.1 % rate only. 

As a result, I believe PNC is either involve false advertisement to lure consumer to transfer their money to PNC Bank and does not honor it 's own promises.