The S&P/ASX 200 Index (ASX: XJO) has rebounded from a poor start and pushing higher on Wednesday. In afternoon trade, the benchmark index is up 0.4% to 8,317.1 points.

Four ASX shares that have failed to rise with the market today are listed below. Here's why they are falling:

AVITA Medical Inc (ASX: AVH)

The AVITA Medical share price is down almost 19% to $3.54. Investors have been selling this regenerative medicine company's shares after it downgraded its guidance for FY 2024. Due to a softer than expected performance in the fourth quarter, the wound care management and skin restoration device seller's commercial revenue is expected to be approximately US$64.3 million for FY 2024. While this is up 29% over FY 2023, it was previously guiding to commercial revenue of US$68 million to US$70 million. AVITA Medical CEO Jim Corbett said: "We remain confident in our long-term growth trajectory as we continue to scale our business. Our strategic investments in our people and new products position us to continue to drive significant growth and sustainable success."

Block Inc (ASX: SQ2)

The Block Inc share price is down 3.5% to $142.64. This follows a poor night of trade for the payment giant's US listed shares on Tuesday. Investors were selling tech stocks after treasury yields increased. This led to the Nasdaq index losing 1.9% of its value during the session. Locally, the S&P/ASX All Technology Index is down almost 1% at the time of writing.

Computershare Ltd (ASX: CPU)

The Computershare share price is down over 1% to $34.69. Investors have been selling this stock transfer company's shares after it was downgraded by a leading broker. According to a note out of UBS, the broker has downgraded Computershare's shares to a neutral rating (from buy) but increased its price target by 13% to $36.15. This implies modest potential upside of approximately 4% for investors over the next 12 months, which is not enough for UBS to maintain its buy recommendation.

GQG Partners Inc (ASX: GQG)

The GQG Partners share price is down 3.5% to $2.09. This fund manager's shares have come under pressure on Wednesday after it released its latest funds under management (FUM) update. The release reveals that GQG Partners ended 2024 with FUM of US$153 billion. While this is up approximately 27% year on year, it has fallen 4.1% since the end of November. This reflects net outflows of US$200 million and a negative investment performance.